There are subjectives, and then there are these. While you may believe a work fits here, and you might be right, people tend to have rather vocal, differing opinions about this subject. Please keep these off of the work's page.
Tyrathius: The Kirby characters were a bit of a Spotlight-Stealing Squad for pretty much the entire game, but there's one moment in particular I thought was really stupid: The beginning of the game. The stadium is attacked by primids, but they are easily defeated by Mario, Kirby, Peach and Zelda. But then Petey Piranha shows up, and somehow manages to One-Hit KO Mario, a character who has defeated him with ease numerous times in his own series. Petey then proceeds to capture Zelda and Peach without a fight, even though both of them are capable fighters in their own right. Yeah, a minor boss is able to defeat three of Nintendo's biggest name characters, for seemingly no reason other than to force you to do the subsequent boss fight using Kirby. Not only is that a bad idea from a gameplay perspective (what if the player just isn't any good with Kirby?) it makes Kirby seem like an unbeatable Mary Sue who trounces threats the other characters can't handle with ease. Even if they wanted the Princesses captured as a nod to their Distressed Damsel roles in their main series, there was no reason to get rid of Mario.
ilovedededeAGAIN: The worst scene in this game is when Luigi gets turned into a trophy. King Dedede, my trademark favorite character in video games (hence my username) turns Luigi into a trophy. Wario then comes along (with trophies of Ness and Peach or Zelda) in his vehicle and plans on taking the Luigi trophy. But then guess what happens: a squad of Waddle Dees come and attack Wario (WTH?) and King Dedede manages to steal Wario's vehicle. King Dedede may be a video game villain, but he's not THAT bad for a villain (compared to Bowser or Ganondorf), so there was no reason the writers of the Subspace Emissary cutscenes had to turn him into a car robber (at least he gets better close to the ending). The worst part, though, is that Wario never gets his car back. The whole plot of the Subspace Emissary would probably change dramatically if King Dedede stole Bowser's car (yes, he has one too) instead, because back in an earlier level he turned Donkey Kong into a trophy. It would actually be better than stealing Wario's car, since Wario looks like a weak fighter, compared to Dedede himself and his horde of Waddle Dees (don't forget his hammer). Wow, Sakurai. You really did it this time.
ShiningwingX: It gets even worse as the game goes on but the biggest kicker for me has to be toward the end. After all the characters are turned into trophies by Tabuu's Death Ray attack, who among them turn out to be the ones to save them all, and without whom the bad guys would have won? Kirby, and King Dedede. Somehow, Dedede had more insight into what was really going on than any other character and PLANNED for this with the revival badges. Up until this point Bowser and Ganondorf are known to have much more internal knowledge and involvement in the plot, especially with the scenes showing Ganondorf frequently speaking to Master Hand himself (who, we discover is being manipulated by Tabuu. Throughout the course of the story Dedede is shown to be just above Wario when it comes to being in the know so how in the WORLD could he have figured things out so easily when even Ganondorf was unable to? Its never explained but for an extremely vague explanation by Nintendo on the game's website, which mostly boiled down to "He just knew". As for Kirby, how does he manage to wake up and save the day after being blasted by Tabuu along with everyone else? He just eats the revival badge.
Ninetails2000 Dedede stone Wario's trophies to add to his army of fighters for when the shit inevitably hit the fan concerning the subspace army. He knew of Tabuu's plans and was trying to prepare a group of trophyfied fighters to use his revival badges on. He targeted Wario because he was riding around with a truckload of trophies, and he never comes into contact with Bowser. It is understandable for Dedede's actions to be interpreted as simple trolling, as it was cut from the game proper and only explained on the dojo website...which was promptly removed in favor of a new website for the new installment.
genericity The Showdown in Melee was a good final event because the characters you were fighting were thought of as evil and Mewtwo and Ganondorf play together excellently and Giga Bowser alone is a force of nature. What was Brawl's answer to this? A fight against Sonic, Snake and a giant Mario. The event is easy, the characters have no connection to each other and the AI is unexceptional. It just seems like a way for Sakurai to glorify Sonic and Snake's presence. And to add insult to injury there is a pathetically easy event where you fight Ganondorf, Dedede and Bowser together.
cookieman: Oh I thought this event was extremely anti-climactic as well. The point of the event was to illustrate the three companies: Nintendo, Sega, and Konami. Nintendo was considered the "big" company so Mario was big. I thought it was a stupid event too. I also hate the two-player version where you fight the villains and anti-heroes. I do however think the very last event of the Two-Player mode is a fun one (Fighting off every single character).
Ninetails2000 Brawl is a magnificent installment in the series, and nearly every part of it is brilliant!...But...the one thing I can't overlook is the blatant bias against the king of koopas. Bowser is always a big name whenever he pops up, a big threat when portrayed seriously and, in cases where he's part of a group, he usually acts as the Axe CrazyBig Fun. Not here. Here, he's stuck doing anything and everything any other villain could be doing. The only part of his iconic nature that's actually used is his Koopa Clown Car and his penchant for kidnapping princesses over anyone else. This is incredibly infuriating for Bowser fans such as myself who were expecting him to be a more active antagonist for Mario. His fight against Dedede is the closest he gets to his typical Axe Crazy personification as well, which ends with him on the receiving end of not just a swift beatdown, but a dismissive bitchslap for his efforts. Don't get me wrong, he does play his part in the story, but it always felt like he didn't get as much development as he could have in the story.
IthoughtyouwereLuigi The thing that I really hated about the story in Brawl was how confusing it was, the only time I could get what was going on was at the beginning. It especially got confusing by the end where none of the previously established villains were even the main villain,not even Master Hand was the main villain!Instead we get Tabuu, who not only makes no sense, but also broke the already well established "just a kid playing with his toys" theme, and that is what ultimately made me mad.
Cookieman: Subspace related, but something that really bothers me to this day is when Pit/Mario and Yoshi/Link join teams? When Mario/Link sees the other team defeat the opposing princess, they attack them ... not too bad, but why the heck would Mario and Yoshi not acknowledge each other and probably explain that it's a misunderstanding. At least there's a scene later on in the game where Mario actually rides on Yoshi.