These are what we call the 'YMMV items.' Things that some people find in this work. We call them 'your mileage might vary' because not everyone sees these things in the same way. This starts discussions in the trope lists, a thing we don't want. Please use the discussion page if you'd like to discuss any of these items.
Anvilicious: "Nothing in this world is the way it oughta be", season 4.
Also, Billy Blim. A man so monstrous, so vile, that he deserves his own special prison dimension. What's his crime? Misogyny.
Base Breaker: Illyria. On the one hand she had a lot of Replacement Scrappy heat to shake off and it didn't help that she was introduced towards the end of the series. On the other she is very cool and very well played by Amy Acker.
It also helps if you know that if the show hadn't been cancelled, season 6 would have Fred turn out to be Not Quite Dead and fighting Illyria for control of her body, meaning Illyria didn't comdemn her to death without an afterlife.
Cordelia's role in the fourth season is a gigantic wankfest over the extended rape and murder of a beloved character with, like Wesley, some of the best Character Development on the show, from an awful The Libby to a phenomenal feminist hero rivaling Buffy herself.
Bizarro Episode: Some viewers consider "The Girl In Question" to be this - in the middle of a tense, tragic story arc leading up to the heavily depressing series finale, we get an episode revolving around Spike and Angel gallivanting off to Italy to have wacky, Ho Yay-tastic adventures while trying to rescue Buffy from the mistake of dating an unseen, vampiric sexual predator with whom they apparently have a never-before-mentioned complex history; this unapologetically farcical storyline is played against a bitter, tragic Los Angeles subplot in which Illyria assumes Fred's form in order to deceive her parents into believing that their daughter is alive and well, a state of affairs which nearly breaks Wesley and is difficult to watch even for the viewers. The episode feels fragmented and out of place at best, and at worst features an incredibly tactless and offensive juxtaposition of storylines.
Marcus from season 1's "In the Dark" is hired by Spike to extract information from Angel on the whereabouts of the Gem of Amarra, a magical ring that gives Vampires complete invulnerability from harm and their usual weaknesses, such as sunlight. A man obsessed with the "art" of torture, Marcus is rumored to have inspired some of the more favored and gruesome techniques used through history. Serenely, playing Mozart in the background, Marcus falls into a rhythm of torturing Angel, impaling him with hot pokers then asking Angel what he truly wants. When Angel refuses to answer, the cycle begins again, each time with Marcus hoping to truly break Angel and lay his soul bare. He also burns Angel with sunlight and forces him to suspend himself in the air with his chains in order to avoid being incinerated. Marcus is also a pedophile who specializes in feeding on and molesting children, and, after Marcus betrays Spike and takes the ring for himself, the first thing he does with his newfound invulnerability is attempt to murder a group of boy scouts, only being stopped due to the timely arrival of Angel.
From season 1's "I've Got You Under My Skin," Angel and his gang try to exorcise a demon from RyanAnderson that had been causing him to start fires and attempt to murder his own sister. The twist comes when after being ejected from the boy, the demon reveals that it was trapped inside the child's body and the boy was so twisted, cruel, and malevolent that the otherworldly monster was actually afraid of him. Angel barely manages to get to the boy's home to stop him from succeeding in burning his sister alive.
Billy Blim from season 3's "Billy" appears to be a normal young man, but he is actually a demon filled with an extreme power of misogyny and had the power to turn any man he touched or who came in contact with his bodily fluids into someone extremely savage and brutal toward anyone female. He had no real reason to be doing this; rather, he appeared to do it only for his own sheer amusement. The fact that the normally very cold and amoral Lilah took him out says volumes as to how horrible he was.
Crazy Awesome: Faith's second run in the series. How does Angelus saving the world grab you? Or Faith fighting him while higher than a kite, allowing herself to be fed on so he gets so drugged out he hallucinates the good acts he's done, much to his horror?
Among the recurring characters, Skip. He was so popular in his debut appearance in season 3 that he was brought back for 3 more episodes. Joss has mentioned that he finds Skip to be among the coolest demons in the series, at least in design.
Matthias Parvayne to a lesser extent. He only appeared in one episode despite having a bit more of an impact than just one episode, but has a reasonable fanbase considering. He's also considered to be one of the most terrifying villains, which is saying something given the various Big Bads and Dragons he has for competition.
"Funny Aneurysm" Moment: "Eternity" features an offhand comment from Cordelia about how an actress was part of a great show cancelled in its prime. Little did Joss fans know that they would be experiencing the samefate.
Genius Bonus: Holtz comes off as evil to modern audiences, but his beliefs were only mildly conservative in his day — not the least is that he is indeed glad that Angel has a soul now. While modern audiences may view Angelus' soullessness as a valid Freudian Excuse, in Holtz's day, suffering the proper justice for sins committed was a major part of redemption. To Holtz, torturing a soulless Angel would have been empty sadism, though he'd have done it out of revenge anyway; by Paying Evil unto Evil on a penitent man, however, Holtz is also forcing Angel to atone.
God-Mode Sue: Illyria, though she does get de-powered eventually.
Lorne's final line, "Good night, folks." Shortly afterward, Andy Hallett would become so ill from an infected tooth abcess that he would never perform again, and died a few years later.
Hilarious in Hindsight: The interviews Joss Whedon gave before the premiere stating that the show would be more of a "case of the week" show focusing more on guest stars and that it was less of a Soap Opera like Buffy. It turned out Whedon and his writers were not suited to writing those type of stories and the show eventually evolved and became a bigger soap opera than Buffy!
Years before anyone had ever heard of Twilight, Angel had an episode featuring a vampire from Angel's past named James who has an operation to make him temporarily invincible (but which kills him after a few hours) in order to avenge the death of his girlfriend who Angel had killed. The whole episode deconstructs the idea that true love means that you should commit suicide if you lose the other person. So Angel had an episode deconstructing one of the most irritating and controversial aspect of the twilight novels using a villain with the same name as one of the twilight villains years before the other series was even written.
Fred shouts out "Whiskey!" at one point. A few years later in Dollhouse she plays an active named Whiskey.
Connor is raised as Holtz's son, and given the name Steven. That's right, his assumed name is STEVE HOLTZ!
Ho Yay: Angel/Spike, Angel/Wesley, Angel/Lindsey, Gunn/Wesley — most of which is just over-interpretation by fans, although the writers were very much aware of this, especially Angel/Spike (cf: Spike stating that he and Angel have never been intimate 'except that once', which Joss Whedon refers to on a DVD episode commentary — "do you think they never? Come on!")
What about Darla and Drusilla? They take baths together, have a threesome with The Immortal, a man who witnesses their reunion refers to it as a "make out session" and calls Dru Darla's girlfriend and Drusilla calls Darla "my sweet" which is what she called Spike when he was her boyfriend. Julie Benz confirmed the Les Yay between them in her afterellen.com interview.
This becomes Incest Subtext when you consider Drusilla's tendency to refer to Darla as both her "grandmother" and her "daughter."
Played at with a scene in "Disharmony". Harmony attempts to attack Cordelia in her sleep but is stopped when Cordy wakes up. Their ensuing conversation lays heavily on this. Made even funnier when Cordelia calls Willow.
Fred and Willow when Willow arrives to re-ensoul Angel. Mostly on Willow's part and mostly played for comedy. Fred, like everyone else, is comically confused by Willow's behaviour.
Hollywood Homely: An early episode had a monster that switched hosts through sex. It transferred from a male host who looked like an underwear model to a girl who was alternately described as "Sarah plain and tall" and "that dowdy chick" that Cordy declared must be loaded to have such an attractive paramour. She's a gorgeous blonde girl who is no less attractive than anyone else on the show. Ultimately subverted in that the demon really knows how to make its hosts look good, and they all end up looking absolutely gorgeous when it's in control.
Jerkass Woobie: Connor, though at times more of the former than the latter.
Holtz outdoes Them both though. Lindsey and Lilah are no slouches either.
Mary Sue Classic: The Immortal. Loved by his friends, respected by his enemies, made fools of Angelus and Spike, had a threesome with Darla and Drusilla, and is in a relationship with one of the fake Buffys.
Holtz may not a truly evil person, but killing yourself, pinning it on the good guy (granted in a past life he had been evil), and effectively ruining your "son"'s life? Not cool, dude. Others posit he crossed much earlier, when he kidnapped Conner and escaped into another dimension.
Painful Rhyme: In the series finale, Spike reads off this little poem:
My soul is wrath in harsh repose
Midnight descends in raven colored clothes
But soft, behold! A sunlight beam
Cutting a swath of glimmering gleam
My heart expands, 'tis grown a bulge in't,
Inspired by your beauty effulgent
This is a continuity gag to the Buffy episode "Fool for Love" which tells Spike's origin story as a nebbish twit, nicknamed "William the Bloody" for his bloody awful poetry. He reads the poem to a girl he's in love with at a party and is publicly derided as a laughing stock shortly before being rejected. So the fact that he's rereading it with confidence at a contemporary poetry slam and the crowd actually loves him is pretty awesome.
Illyria, for Fred's fans who wanted to see more of her and Wesley being a couple. Not helped by Illyria being one of the most dick-ish characters in the entire Buffyverse.
Rescued from the Scrappy Heap: Connor when he comes back for the finale. Turns out having a normal upbringing made the kid a lot more bearable, and his father-son team up was very well-recieved.
Likewise Cordelia's appearance in "You're Welcome" was very well received by fans and critics. It was actually praised for undoing all the horrible things done with her character during season 4.
Taking the sister series into account, not only does Cordelia count but so does Wesley. The basis of his character is he thinks he is Sean Connery, but is actually George Lazenby. Well the series turned him into Daniel Craig, going from a wannabe big bad rogue demon hunter that the series poked fun at over, to a devoted, driven man so balls to the wall crazy he threatens allies with death, kept the woman who tried to kill him in a cage for months and is almost Jack Bauer-esque in fighting the forces of evil.
Romantic Plot Tumor: Was there any real love behind Cordy and Connor's relationship, or was it just "I want to bone you" on Connor's side and " I need you to impregnate me so that I can bring about the end of the world as we know it" on Cordy's side?
It could’ve been worse: If you thought the hockey speech was bad, imagine if Connor been a girl. Angel was mushy enough with a son; a daughter would have led to some of the most EgregiousDaddy’s Little Girl ever broadcast.
Squick: Alot of people's opinion of the above-mentioned Cordelia-Conor Romantic Plot Tumor, especially considering that Cordelia is virtually Conor's mother and (from her perspective) she was changing his diapers just a few months earlier. also, that is NOTCordelia
Ugly Cute: The squid-hound thing named Pancakes that becomes Illyria's pet in her Haunted miniseries.
Wangst: A lot of Season Three. Most of the time when Darla is around.
Considering the Romantic Plot Tumor, Season Four actually comes off as worse in this regard. Seriously guys... Fighting over Fred when Angelus is sitting in a cage right below your feet and listening to every word you're saying? Really now...
What Do You Mean, It's Not for Kids?: Channel 4 bought the first season in the UK and showed it at 6pm, because, you know, anything with magic in it is obviously teatime fare for kids. Even showing the episodes with cutting severe enough to make some of them barely comprehensible resulted in a formal reprimand from the Broadcasting Standards Council (the then Censorship Bureau, now merged into Ofcom), and the remainder of the first series and the second series were buried in a late-night timeslot.
The Woobie: This is a Whedon show, which means that just about every protagonist fits this trope at some point. The biggest Woobies in the show, though, are Angel himself, Fred, Wesley, and Connor. Even Illyria qualifies, if you're into that sort of thing.