Bolivar Trask's dwarfism in this film has cast his antagonism of the mutant race in this light for some viewers. He either admires mutants and just sees them as a means to an end for protecting Earth, or he hates that he was born with a perfectly ordinary and useless mutation while all other mutants win some form of Super Power Lottery. Note that this is an interpretation Peter Dinklage and Bryan Singer disagree on; Singer brought the theory up as a possibility, while Dinklage was strongly opposed (as he should, the man has made "not playing a dwarf" his life's ambition. And to the movie's credit, no one ever really mentions or even seems to notice that Trask is a dwarf - if he were played by a non-dwarf actor, almost nothing would need to be changed).
Had future Magneto truly undergone a Heel–Face Turn, or was he just stuck in an Enemy Mine situation, in which he didn't so much regret his actions, as the consequences they brought?
Did future Magneto honestly believe 70s Magneto would help Wolverine and co. and that him going rogue was unforeseen, or was it all part of his plan? Though he might not have known how his younger self would react.
Author's Saving Throw: Several examples, to the point this could be called "Author's Saving Throw: The Movie."
Magneto's helmet, while still recolored red from its natural silver color, is a lot darker and a lot less goofy-looking than what he wore at the end of First Class. It applies to the rest of his costume too. Since so many laughed their asses off at his costume back then, it's pretty obvious why the change was made.
Given how poorly X-Men: The Last Stand and X-Men Origins: Wolverine were received by fans and critics alike, them being retconned out of existence by the ending of the movie qualifies. Most fans are content to pretend those two films didn't exist, although some still take issue with it. Mitigated a little by the fact that the events of these movies still happened in the original timeline, and are still remembered by Logan (in fact, the film telegraphs this in dialogue early on), but were changed after the effects of Wolverine's journey settled in.
X-Men and X2: X-Men United were much better received, but for ages people have complained about how Wolverine tended to steal the spotlight from the other X-Men, most notably the team leader Cyclops. Although he's a major player in this film, he certainly doesn't hog the spotlight nearly as much, as much of the ensemble (Professor X and Mystique especially) get a greater degree of screentime. The events of those films may have still happened, but only in Broad Strokes, as the Cosmic Retcon of the movie more or less leaves the revised future a blank slate. This has given the other X-Men their chance to shine in future films, including Cyclops as his death in The Last Stand was undone.
Xavier's fans were extremely annoyed when he was given the Angst? What Angst? treatment in X-Men: First Class after the trauma he had experienced during the climax, so Days of Future Past rectifies this by revealing that Charles had bottled up his emotions as a coping mechanism, but the dam he had placed over his pain finally bursts when he's forced to close his school after a single semester. Moreover, First Class was heavily advertised as containing two lead characters of equal importance, but in truth, Magneto was the main protagonist, so those who liked Xavier more were understandably disappointed. Bryan Singer, a Professor X fanboy, balances out this inequality by giving the younger Charles the most Character Development in the sequel.
A small one, but this film explains how Hank could be Beast in X-Men: First Class, but appear human on TV in X2, and how Xavier could have the use of his legs in X3 and Origins.
Bellisario's Maxim: Producer Simon Kinberg has stated that this movie retcons the entirety of the X-Men film series, including things that it should logically not affect, such as Wolverine having Adamantium claws in the Bad Future after losing them in The Wolverine, or certain characters being born in different time periods than they were originally shown (such as Toad). It sounds more like he wanted to go for a complete Continuity Reboot without calling the movie one.
The Cosmic Retcon done to X-Men: The Last Stand and X-Men Origins: Wolverine due to the events of this film. To some, it's great news because of the lackluster reception those films got, while others who liked those films feel it's disrespectful to the other directors to retcon them out of existence entirely. The status of the first two X-Men films is also up for debate, especially given the more sympathetic approach to Mystique, which is at odds with the murderous Mystique seen early on in the films. The Wolverine is also erased, but since Wolverine still remembers the events of that film, it isn't as bad.
A factor for some is the non-cosmic retcon caused by the "Past" being 1973, instead of our present as in the comic and previous adaptations, which will make it harder for people to rewatch any of the first three movies without thinking, "It doesn't matter who wins here, the Earth has been doomed for over thirty years anyway."
The decision to make Wolverine the main character of the storyline when Kitty Pryde was in the comics. It makes more sense with the movie series's established plotline (Wolverine is sent back via Mental Time Travel to the 1970's and Kitty hasn't been born yet), but it's still a bitter pill for Kitty fans and people who wanted to see another X-Men movie where Wolverine was NOT the main character. Of course, it also goes in reverse; many fans who have stuck with the series since the release of X1 have argued that the film would have had a drastically reduced emotional impact if we had Kitty instead of Logan, seeing as how little screen time she had in the previous movies. Although Logan's role in the movie is fairly minor; in the 1970's, he takes a backseat to Charles, Erik, and Raven.
Some reviewers of The Rogue Cut thought the new scenes helped flesh out the story and characters, while others saw them as Padding that ruined the pace.
Continuity Lock-Out: Very few would argue that the film strikes with full impact if one has skipped some or all of the other X-Men films. At the very least X-Men: The Last Stand, which explains Logan spazzing out over the random redhead (a very much alive Jean Grey) at the end and X-Men: First Class, which explains... everything else.
Crazy Awesome: Quicksilver is a kleptomaniac that relies on constantly being stimulated. It doesn't stop him from being one of the most effective characters in the entire movie. This is best shown during the escape from the Pentagon, when he spends much of the time goofing around with the security team instead of deflecting the bullets headed at the protagonists while using his super-speed.
Creepy Awesome: The Stinger, where Apocalypse stands over a crowd of people chanting his [real] name, while he telekinetically constructs a pyramid in about 15 seconds.
Dancing Bear: The omnipresent Stan Lee does not make any cameo in the film. He explained that "It also could be they didn't want me to do the cameo because, without my cameo, the movie will make more money... You see, somebody watches the movie and the movie ends and the person says, 'Wow, I didn't see Stan's cameo. I must have missed it.' So what do they do? Right back to the box office, buy another ticket, and watch the movie again. So I think it's a big moneymaking ploy on the part of the producers."
Even with all the Fandom Rivalry shenanigans and costume grievances over Quicksilver, he ends up stealing the show when he's on screen.
Blink is one of the highlights of the movie because of her unique look and creative uses of her power in the action scenes. Most fans predicted this, since the character's comic counterpart is already a pretty big fan-favorite, and for the exact same reasons, no less.
Even Better Sequel: While First Class was well-liked by fans for bringing the X-Men series back on track, DOFP has been even more well-received and cited by a few reviewers as the best of the X-Men movies. It even currently has the highest Rotten Tomatoes score in the series at 91%, placing DOFP among the best-reviewed Marvel movies of all, Marvel Cinematic Universe or otherwise. The movie has also become the top-grossing X-Men film in terms of worldwide box office by far, usurping the position previously held by The Last Stand.
As with Sony's Amazing Spider-Man films, many fans of the Marvel Cinematic Universe criticize this film just for existing and maintaining Fox's hold on the X-Men film rights, since they wish the rights would go to Marvel Studios. All the more since the Marvel Cinematic Universe version of Quicksilver had already appeared in Captain America: The Winter Soldier and later in Avengers: Age of Ultron. And then there are accusations of Marvel trying to undermine Fox's success by downplaying its X-Men marketing in the comics and cancelling its Fantastic Four titles, while playing up lesser-known concepts such as the Guardians of the Galaxy and Inhumans that will appear in its upcoming movies.note This is something it isn't doing with Spider-Man, for obvious reasons, but Marvel is known to be on better terms with Sony than with Fox as well. Given that most of these franchise's box office draw comes from movie goers and not comic fans, however, one has to wonder how people got this assumption.
Note that this MCU rivalry is different for X-Men than for The Amazing Spider-Man (which has a Fandom Rivalry with DOFP in its own right). Due to DOFP's very positive reception, the rivalry is less "they're turning the series into a Franchise Zombiejust to hold on to the rights"note a criticism of The Amazing Spider-Man 2 by some fans and more "which Marvel movie series/universe is better".note If you want to get technical, it's also often argued that the concept of X-Men works better in their own universe, since it wouldn't make sense why the Avengers are so respected yet mutants are segregated and hunted — a reason why Simon Kinberg has stated thatFantastic Four (2015) won't take place in the X-Men universe.
"Funny Aneurysm" Moment: The bittersweet but somewhat hopeful endings of X-Men United and The Last Stand are now significantly less so due to the (non-cosmic) retcon in this movie, which essentially reveals that the future of relations between mutants and the rest of humanity were always doomed, due to events set in motion decades before the first movie.
The final scene in X-Men: First Class (in which the young Magneto begins his Start of Darkness by rescuing Emma Frost and giving his nickname for the first time) seems a lot more grim when you realize that most of the people standing in the room with him (save for Mystique) died offscreen between films, and no one besides Erik or Mystique giving a damn about their deaths.
In X-Men, Mystique injected a substance into Cerebro that was either meant to put Xavier into a coma or kill him. Now that old Xavier himself confirms that he and Mystique grew up together, it turns her actions in the first film into a cruel betrayal. Mystique had fallen so low that she had no emotional problem with putting her adoptive brother into a coma and possibly killing him just to further an agenda.
However, this is one of many things that may now no longer have happened due to the Cosmic Retcon.
She may have had an emotional problem. Someone with her abilities could have used a much more lethal poison, or a bomb, to ensure that Xavier dies. Instead, Mystique used a drug which the professor would have a fair chance of surviving.
When Erik offers to play chess as a peace offering to Charles during the plane ride to Paris, it's not just because he feels guilty for losing his temper earlier, but he knows that this is his last chance to bond amicably with Charles before carrying out his plan to murder Mystique. If it were successful, Xavier would never forgive him for killing his beloved sister, so Erik believed at the time that he'd lose any hope of reconciling afterwards.
Professor X's line "Experimentation on mutants—it's not unheard of" in X-Men becomes more chilling when you take into account Bolivar Trask's examination and dissection of mutants in this movie. Xavier would be thinking more specifically of Banshee's death and the torture Mystique endured before she managed to escape Trask Industries in the original timeline.
When Bobby informs Logan in X2: X-Men United that there is no beer at the school, it's obviously because Professor X doesn't want to encourage underage drinking, but there is an additional reason for the alcohol-free environment. This installment reveals that Charles was a drunkard in between 1963 and 1973, so naturally his older, wiser self doesn't want to be tempted by drink and risk a relapse.
We learn that Xavier harboured a Dark Secret from his childhood (i.e. mistaking the onset of his telepathy at age nine for a severe mental illness). While it's hinted in X-Men: First Class that his mother is an innately cold person, at least some of her aloofness can be attributed to the very strong stigma which existed around psychiatric disorders in the 1940s. No wonder Raven was Charles' oldest and only true friend—she was the sole individual in his social circle who didn't consider to him to be a "lunatic" because he heard voices in his head.
Near the end of X2: X-Men United, Stryker's grave warning is, "One day, someone will finish what I've started!", and mutant genocide actually does become reality in this movie. The colonel wasn't making an empty threat at all; he was plainly aware of Trask Industries' progress on the Sentinels, and he knew it was only matter of time before the robots were sophisticated enough to slay even the most powerful mutants.
In The Rogue Cut, Ms. Maximoff is seen consuming alcohol while watching TV in the middle of the day; in X-Men: Apocalypse, she's holding a drink during daytime while talking to her son Peter. It's bad enough that Quicksilver grew up without a father; living with an alcoholic mother definitely can't be easy. One of the reasons why Ms. Maximoff is drowning her sorrows is because she's bitter at Erik for abandoning her before Peter's birth, which would've been in the mid-1950s, when unmarried women with children were treated like social pariahs.
Professor X reassuring Beast in X-Men: The Last Stand that "You are always welcome here. You are a part of this place" becomes that much sweeter when you take into account their close relationship in this movie.
The first movie has Professor X telling Logan, "I give you my word that I will use all my power to help you piece together what you've lost, and what you're looking for." Wolverine doesn't know it yet, but what he's truly looking for is right in front of him. As X-Men: Days of Future Past demonstrates, Xavier is the person who gives meaning to Logan's existence; the "master" to his "samurai," so to speak. This is especially true in the Alternate Timeline, where Wolverine has settled down as a history teacher at Charles' school, and is genuinely happy—probably the happiest we've seen him in the entire film franchise. Days of Future Past makes it clear that it's Xavier—and not Jean Grey, as The Wolverinemight have you believe—who is the most significant figure in Logan's life during his post-amnesia years.
McCoy asks Charles, "Are you sure you should've let them [Magneto and Mystique] go?", and Xavier's reply is, "I have hope for them. There's going to be a time, Hank, when we're all together." He's half-right, because Raven does come home to him in X-Men: Apocalypse as his team's Number Two. Although Erik doesn't stay after he helps Jean to rebuild the school, he and Charles do reconcile, and Lehnsherr's farewell hints that he'll return to visit some day.
The farewell scene between Xavier and Peter turned out to be an important piece of Foreshadowing because Quicksilver becomes Professor X's protégé after the Final Battle of X-Men: Apocalypse. In 1973, it was Charles (and not Erik, who was the subject of the prison break) who had thanked Maximoff for his help, gave the teen a task which required some responsibility (i.e. returning the rental car), and offered him a paternal-sounding "Take it slow" as a goodbye, which made Peter grin. That small gesture ended up carrying a lot of meaning because Quicksilver chooses Xavier as his Parental Substitute over his own father a decade later.
The comic book crossover between the X-Men and the cast of Star Trek: The Next Generation had members of both cast having to deal with interferences to the Battle of Wolf 359 and Days of Future Past. Captain Picard was among those arriving in the DoFP timeline, technically making it Stewart's first experience in a world dominated by Sentinels.
The parents of Bobby Drake were horrified in X2: X-Men United when they thought that Wolverine was a teacher at the mansion (which was just Wolverine's convenient excuse at the time). Now, he is a teacher, for real. And who says that Bobby was not one of his students?
The reaction to Quicksilver, in a manner largely unrelated to the issues with his upcoming appearance in the Avengers sequel; many took exception to what appeared to be terrible visuals for the character when some of the still photos and character shoot images were revealed, and stated that they would wait for Whedon's sequel for a 'true' take on the character. Cut to the film's release, and it looks like Whedon actually has a pretty high benchmark to meet, given Singer's Quicksilver has been embraced by the audience.
Considering that Xavier can easily use Magneto as a marionette as long as the latter doesn't wear the telepathy-blocking helmet, his words of encouragement in X-Men: First Class ("When you can access all of that, you will possess a power no one can match. Not even me") now sounds rather hollow. It comes off as a little white lie that he made up on the spot in order to try to help Erik achieve the correct point between rage and serenity. In their natural state, Charles' ability is stronger than Erik's, no ifs, ands or buts about it. X-Men: Apocalypse further reinforces this point by depicting Professor X as the second-most powerful mutant in the story after Apocalypse (third after Jean releases the Phoenix Force), and the eponymous villain waxes poetic about Xavier's psychic powers, calling them "extraordinary" and the best gift that he had encountered in "a thousand lifetimes."
It's implied in a later scene that Hank is a Trekkie, so calling Peter's power "fascinating" was his attempt to emulate Spock, who is presumably his favourite character on Star Trek: The Original Series.
Anyone who is a fan of both McAvoy's Xavier and Will Graham from Hannibal will notice the striking similarities between the two characters. (You can read a more detailed comparison in the Shout-Out section on the main page, but for the sake of this entry, it's enough to know that Will is a "pure empath" who is physically and emotionally scarred by his abusive love-hate relationship with the murderous Hannibal Lecter—heck, Hugh Dancy and James McAvoy even look somewhat alike.) The X-Men fandom coined the term "Mutant husbands" to describe Charles' and Erik's homoerotic friendship, so all Cherik shippers who had watched the Hannibal episode "And the Woman Clothed with the Sun..." burst out laughing when Freddie Lounds called Graham and Lecter "Murder husbands."
Six years after Wanted, James McAvoy accuses someone else for committing assassination because the bullet curved.
Professor X and Bolivar Trask once worked together in Penelope.
The reason why Stryker can tell that "Wolverine" is an impostor in X2: X-Men United is because the former had a scuffle with Mystique in 1973 when she freed mutant soldiers who were meant to be transported to Trask Industries. Stryker had witnessed firsthand her shape-shifting abilities.
Anyone who watches Days of Future Past before Working Girl would chuckle whenever the characters in the latter discuss Trask Industries.
Although Legion (2017) takes place in a parallel universe which is distinct from the movie-verse, the show nevertheless alludes that David Haller is vaguely connected to Professor X (the former is the latter's estranged son in the comics). David also assumes he's going crazy when his mutant ability first manifests because he's Hearing Voices. Both characters also sport Messy Hair to denote their psychological instability.
When the younger Charles loses his temper with Erik on the plane, his outburst demonstrates quite clearly that Erik's betrayal in First Class (where their friendship had only lasted a few months) had hurt him a lot more than Raven's (who grew up with him as a sister figure for 18 years).
Charles: YOU ABANDONED ME!!! You took her away, and YOU ABANDONED ME!!!
When Logan asks Hank as to why Charles is in such bad shape, Hank lists Erik before Raven and the spinal cord injury, implying that the loss of Erik upset Charles more than the other two.
Hank: He lost everything: Erik, Raven, his legs...
After Charles punches Erik very hard in the face, not only does Erik not retaliate at all (it's extremely rare for him to not respond to violence with violence), but he simply wipes his mouth where he was hit as he cheerfully greets Charles without any sarcasm. After believing for 11 years that he'd never see Charles again (and 10 of those were spent in solitary confinement), Erik is so darn grateful to be in Charles' presence once more that he isn't the least bit angry by the latter's punch.
Erik: Good to see you, too, old friend.
Without any context, this scene would look like Erik and Charles are engaged in a romantic Held Gaze. This io9 article mentions "Young Professor X and Magneto smoldering at each other!" as one of the highlights of the trailer.
Considering that chess is sometimes used as a metaphor for romance and sex, there is a slight Double Entendre when Erik attempts to persuade Charles to join him for a game of chess as a peace offering.
Charles: It's been a while since I've played. Erik: I'll go easy on you.
Ian McKellenwishes there was a scene of Erik making love to Charles... only to reveal that "Charles" was Mystique in disguise. (So what the actor is suggesting is that Magneto only became romantically involved with Mystique because he couldn't have Xavier.)
McKellen: I thought it would be wonderful to have a scene in which you saw Magneto waking up, probably making love to [...] Mystique, and it would begin with Magneto making love to Professor X who turns into her. Wouldn't that be fun?
Hank staying behind with Charles and taking care of him for a decade. James McAvoy even joked about the inherent slash-iness of the two characters in this interview.
McAvoy: Hank is my enabler and my bitch.
There's a brief moment in the Gag Reel on the Blu-Ray/DVD release where Nicholas Hoult lifts James (who is much shorter than his younger co-star) into his arms and performs a Bridal Carry.
Hype Backlash: The film is hyped as being both a return to form for the X-Men films, mitigates all the troubling qualities of the previous installment, and is said to be as good as the Marvel Cinematic Universe films; in other words, its very, very hyped up. For some, it really doesn't live up to it, especially those who still see many of the same issues as before creeping in.
Mentor Ship: There has been a small, but noticeable increase in Charles/Logan◊ shippers thanks to James McAvoy and Hugh Jackman sharing a lot of screentime together. It's a pairing that works both ways because Logan counsels the younger Xavier in this movie, but Professor X is Wolverine's mentor in the original trilogy.
Moral Event Horizon: Much of the film's plot is built around Charles, Hank, and Logan trying to prevent Raven/Mystique from crossing her (In-universe) MEH of killing Trask. Erik tries to stop her at first, but tries to push her into murdering humans when her blood is taken anyway.
Magneto names the mutants who have died when he lashes out at Professor X for the latter's apathy and inaction. But it falls rather flat when — except for Sean Cassidy — every character he mentions supported Sebastian Shaw, the villain in First Class, in his nuclear winter plot, and had attempted to kill/successfully killed Xavier's proteges. Xavier has little reason to mourn for their loss, or feel regret that he didn't help to save them.
The future Sentinels dispatch their enemies in such hilariously over-the-top ways that it can be hard not to snicker.
At one point, a character (Mystique) screams "Get out of my head, Charles!" when Professor X is trying to reach said character. While the scene it's in is dramatic and well-acted, the Narm kicks in if you have seen "The Juggernaut, Bitch!", in which that line is one of Juggernaut's many catch phrases.
There's only so many times you can stand dramatically in one place, arms out, palms up, while stuff just floats around you before it becomes silly. This goes for Magneto and Apocalypse.
Also, Magneto's aerial propulsion onto a train towards the beginning of the third act via pelvic thrust.
The Army Colonel Mystique impersonates sounds... odd.
James McAvoy is a great actor and can bring a lot of intensity to his lines. Perhaps too much at times. Like "So...Much...Puh-AIN."
For anyone who understands Vietnamese, Mystique's scene with the VN general was ridiculous; she spoke with a heavy, barely discernable accent, and yet he praised her as if she spoke like a natural. Of course, he is currently trying to get into her pants at the time...
"What's the matter baby? You don't think I look pretty like this?" Cue a lot of snarky comments that Jennifer Lawrence in blue makeup is still hot no matter what the film says.
Narm Charm: The 1973 scenes may look a tad colorful and flamboyant, if not outright dorky, to a 21st century audience. But they really do give an authentic '70s feel and even add to the tension.
Older Than They Think: This film introduced mainstream audiences to the character of Blink, whose power is essentially to create portals. This resulted in many people saying the character must've been inspired by the video game Portal, even though the character Blink predates that game by over a decade.
Quicksilver appears briefly to help break Erik out of prison, being both marvellous and hilarious in the process.
The guy in The Stinger (Apocalypse) also leaves a mark.
While they appear in several scenes, most of the future mutants appear for such a small amount of time, but have such impressive fight scenes that it can lead to this.
Only the Creator Does It Right: Cemented by having Singer back in the director's chair and getting an overwhelmingly positive reception, with many calling it the best in the franchise so far.
Overshadowed by Controversy: Inverted, oddly enough. The critical and commercial success of the film was able to overshadow director Bryan Singer's sexual assault allegations (which were subsequently dismissed).
Making Kitty the key to sending people into the past may have been an attempt to placate the fans who were mad that Logan was sent back instead of her. In this case, it's something that only pleased some of the base.
Before the movie's release, Evan Peters' portrayal Quicksilver was already being highly criticized for a) not being the same as Aaron Taylor-Johnson in Avengers: The Age of Ultron and b) his costume, which many called ridiculous. When the people got to see him in the film, the public's opinion of him changed radically after the Pentagon kitchen scene.
Ships That Pass in the Night: Blink and Warpath have been fairly popular with fans, despite the two of them not sharing any dialogue with each other.
The special effects are extremely top notch, but there are times when the '70s-era Sentinels (notably the one that Magneto places metal into on the train) look off.
In the stinger, Apocalypse's pyramid-forming looks a bit on the Conspicuous CG side.
The triumphant moment of Mystique smiling at Xavier and Beast after refusing to kill Trask is somewhat marred by the dodgy CGI effects used on her eyes when she looks over at them. The compositing of the CGI makes it look like she's going cross-eyed.
Beast, where in his other appearances looks very feline, here looks like Teen Wolf...
Guy gets sent to the past to save someone whose death is a crucial factor in the current Robot War. Sounds familiar... However, the film is based on a comic book that pre-datedTerminator. And Bryan Singer even asked James Cameron for advice on pulling off time travel.
Ever wondered what a big-budget Portal movie adaptation would look like? Blink's fight scenes give you a pretty damn good idea.
Strawman Hasa Point: The film presents the inverse of the situation seen in X1. This time, it's the government who takes the side of the mutants at Trask's Senate hearing and refuse to give the funding he needs to create the Sentinel program. The problem is that Trask has very well-founded fears that the audience can sympathize with. He correctly points out that the U.S. and Russia nearly went to war in the course of a single battle as a result of mutant intervention (which they officially deny, but are later seen to have removed several pieces of clothing and technology from and stored). After the Paris Peace Accord incident, he then points out that the participants include a man who can direct metal (and is the prime suspect/convicted prisoner in the death of a sitting U.S. President), another who believes that mutants will drive humanity into extinction, and a third who can shapeshift into anyone and order a nuclear strike if she felt like it. It doesn't justify his genocidal tendencies towards mutants, but there are some very real fears.
Wolverine being the one to travel back in time rather than Shadowcat, who did so in the original storyline. Part of the reason this causes backlash is that Shadowcat's role has been played by another character before, by Bishop in the 90's cartoon (presumably in an attempt to capitalize on the then-recently introduced character's popularity). Not to mention the Professor more-or-less filling the role in Wolverine and the X-Men.
Pietro being renamed 'Peter' to Americanize him is also a point of contention for some. Especially as it comes after the many times the films have turned non-American characters into Americans, including changing their names to more American sounding ones.
The only mutants in the future who get any meaningful dialogue are Xavier and Magneto, with the rest essentially being glorified cameos, even established characters like Storm, Iceman, and Kitty Pryde. This is mostly a result of several scenes cut from the film in order to keep the runtime short.
Those hoping for more of the First Class mutants in future installments had their hopes dashed when nearly all of them were killed offscreen. Unless said characters are revealed to be Not Quite Dead (which certainly could happen with Emma Frost as she was not among the autopsies of confirmed dead mutants) or come Back from the Dead, they aren't going to be used again—which is a bit strange when you consider that this movie resurrected every other character.
Wanda Maximoff / Scarlet Witch is reduced to a baby Mythology Gag rather than exploring her as a character and relationship with Quicksilver and Magneto.
They Wasted a Perfectly Good Plot: At the end of the film, pre-Adamantium Wolverine is shown being dredged out of the Potomac River and released into Stryker's custody. Only it's not actually Stryker, but Mystique in disguise. Stryker getting his hands on Logan in such a manner would have been the perfect way to maintain the connection between their characters and subject him to Weapon X.
Unfortunate Implications: It's been suggested that the casting of Peter Dinklage as Bolivar Trask was an attempt to invoke unfortunate implications; by insinuating that his hatred of mutants is due to bitterness that he has a genetic mutation that gives him dwarfism rather than being telepathic or able to manipulate metal. Though he admitted it was on the edge of bad taste, Spoony felt the implication added depth to the character. It should also be noted that Peter Dinklage disagrees with this interpretation. (One of the greatest challenges for dwarf actors is finding characters who are not defined by their dwarfism.)
There is no doubt Mystique is a heroic figure in the movie. By the '70s, she is the only one who actively works for the mutant cause and does things like rescuing Alex's unit from being experimented on by Trask. However, her assassination plan needs work. She consistently chooses to attack Trask at very high profile events like the Paris Peace Conference and the Sentinel demonstration in Washington DC, where security is typically tight and she has a higher risk of being killed and/or captured, which is exactly what happens in the original timeline when Charles Xavier isn't there to talk her out of killing Trask. Also, the fact that she's so determined even when she's flat-out told that it's going to end badly. The first attempt can be semi-justified by her having found out about her friends' deaths the night before (and therefore probably acting rashly). The second however...as the Honest Trailers puts it:
"Mystique, a mutant so stubborn, she'd rather cause the apocalypse than listen to reason. (Cue montage of Mystique staying determined to kill Trask even when Magneto and Charles both try to talk her out of it.) When your psychic friend, his mortal enemy, and a dude from the future are all telling you the same thing, you should probably listen to them, idiot."
Magneto deciding to try and kill Mystique is hypocritically in-character for him. The stupid part is doing it in front of two people who would be capable of kicking his ass for trying it, one of whom does and comes very close to killing him. Certainly he could have waited for a more advantageous location to do it, like their metal plane. Even if he succeeded, it still would have resulted in Trask getting her body. You know, that thing that we know he studies to get his Sentinel project running?
Despite having the same age rating as most other superhero films, the film goes so far with some of the deaths in the Bad Future that it should have received a higher age rating. The opening scene is disturbing and highly non-child-friendly.
Wolverine's naked ass, after getting out of a bed that was also occupied by a naked woman.
Win Back the Crowd: With the success of The Avengers (2012), some fans began clamoring for the X-Men characters to return to Marvel Studios. Aside from the obvious crossover potential, those fans thought that Fox wouldn't be able to do the series as much justice as Marvel would. It was then up to Fox to prove that they could. Word of God from the creators was that the film was specifically conceived as an "apology" to everyone who was disappointed with X-Men: The Last Stand.
Charles. His whole world has collapsed around him, he's plagued by bad dreams, and has basically become a drug junkie. He is very clearly in need of major hugs.
Everybody in the bad future. They've clearly been through hell and especially Bishop, since he's usually the one who goes back in time to warn the rest of them after a Sentinel attack. It gets into Nightmare Fuel territory when you think about how many times he must have had to hear his friends being brutally murdered behind him while hoping that he and Kitty will be fast enough to alter the timeline.
Future Magneto when he holds Xavier's hand as he's dying and laments that they wasted so many years fighting each other when they should have been working together all along.
Raven, who has had many former friends killed, sees what they were put through For Science!, and wants to kill Trask for it, and still shows herself to be very conflicted and uneasy about doing it.
Wolverine. His life has been one tragedy after another. Despite Past!Charles being in a terrible place, his reaction to reading Logan's mind is one of shock and sympathy.
Charles: You poor, poor man.
Kitty, who gets sliced to hell when Logan freaks out in the past and spends the rest of the movie trying to hold him there while slowly bleeding to death. By the end, she's openly crying in pain, but she doesn't let go. The Rogue Cut changes this. She still gets stabbed, but is only able to hold on for so long before Rogue is brought in to replace her. Rogue mentions to Kitty that Bobby didn't make it, which only increases the grief in the room.
In The Rogue Cut, Rogue has spent years being experimented on to further the Sentinel Program and the moment she is freed doesn't mean she's any better off. Especially since her ex-boyfriend is killed in front of her eyes. Also, watch her face when one of the sentinels bursts into the monastery, ready to fire. She knows it is the end.
Thankfully several of these tragedies are undone when the Bad Future timeline is erased.
Magneto's chest piece gets flak for looking cheap and silly. Also, Magneto of both past and future has a cape with one half full and the other half only a half cape, making some bizarre 3/4 cape. It sort of makes sense for Future Magneto (fashion choices are limited in a Bad Future), but then his 70's self rolls out with it and we're left to assume that, no matter how many options Magneto has, he just has no taste in clothing.
While the mostly dark or black future outfits aren't bad by any means, there have been a lot of complaints for them being rather dull and unmemorable. This is a problem people have had with the costumes since the first film, with the exception of the blue and yellow costumes from First Class.
Quicksilver's outfit also generated a lot of grumbling over the silver jacket and such, although this dialed down after the movie's release.