Well, since I'm hearing everyone from critics to online people to my friends talk about how much they love the game, I feel like I should go on a rant on why I hated it, because I'm a bitter prick who hates your joy.
1. Iron Man's character does another nonsense 180 like going from "Witty Banter during Alien Invasion" to "PTSD". From telling the government to fuck off and keep their hands off his suits in Iron Man 2 to being a complete stooge in this. Why? Is he lambasted for creating Ultron? No, a random woman just tells him about his dead kid. Does this make realize he's screwed up trying to create Ultron? No, he blames the entire Avengers for destroying Sokoyviev, which they did to save the entire world. The movie ends with him, one of the smartest men in the entire world, having a tantrum because someone killed his parents WHILE brainwashed, because of EMOTIONAL.
2. Ant Man is giant. His name's Ant Man. His powers dictate that by shrinking, he becomes stronger because his power's concentrated or something. When he grows bigger, he's also incredible strong. Hank Pym could do it, but this makes it incredibly clear he's not Pym.
3. Vision sucks. Despite having an Infinity Stone stuck in his head, that grants him incredible power, his role in the Airport fight is little more than weirding out Giant Ant Man and taking out a member of his own team. Come on, Vision!
4. The first few fight scenes were too fast and had weird camera shots, the Airport scene felt less like a brawl between groups and much more like several small fights that didn't interact with each other except for Scarlet Witch.
5. The high scale security footage is easily tricked by the guy who framed Bucky.
6. The Villain is a generic bad guy who wants revenge for his family, who would've died if the Avengers did nothing, yet doesn't single Stark out for creating Ultron.
7. The movie seems to be trying to balance the pure humor of something like "Guardians of the Galaxy" and "Avengers 1" while taking a "Watchmen" or "Dark Knight" analysis of superheroes, and it fails at both. It's one of the least funny Marvel movies, although it has OK bits, but has less banter and includes attempts at comedy like "Ha, your aunt's hot". It's attempts at analysis fail where they try to point out how the heroes are causing the villains a la Dark Knight, yet fail to recognize that the only time the Avengers as a whole have ever screwed up is a dozen dead people in Wakanda while they've saved the world countless times, and the only ones to screw things up are Stark and Banner.
8. They attempt to cram too many characters in the movie, which both is a disservice to the characters and kills all actual character development. They change character motivation's abruptly, like Black Widow and Stark now supporting Government control even though Widow just witnessed the Government secretly being filled with Hydra, and then call that abrupt change "development". Characters like Hawk-Eye seem to just pick a side with a coin flip with no motivations explored, and are only crammed in there because that's the main appeal of the movie, which is "ALL the super heroes".
The Movie wasn't bad, but to me it was only OK, and the fact that everyone else loves it just makes me hate it more.