1. I think the Movie is overrated at 90% on Rotten Tomatoes. I’d put it at 60-70% (notably less awful than the year’s other superhero-vs-superhero movie, Batman vs. Superman, but probably the worst-written MCU movie not starring the Hulk).

2. My biggest complaint against the movie is that it guts well-established character development for no readily obvious reason.

• Iron Man’s the biggest offender. He spent most of his first 3 movies and Avengers 1 establishing himself as a refreshingly cocky genius notably unwilling to cooperate with soulless authority figures even when it was easy to do so (e.g. refusing to falsely deny he was Iron Man and refusing to give his technology to Congress and the military). In this movie, that not only gets completely obliterated, but he becomes the soulless authority figure, which is insult on injury. For example, when a faceless State Department employee blames him for her son getting killed while building homes in the generically Eastern European place that got annihilated during Avengers 2, is there ANY evidence from earlier movies that suggests the actual Tony Stark would think “Wow, that’s a great reason to submit the Avengers to faceless UN bureaucrats that I don’t know and have no reason to trust?” I think he’d be a lot more likely to point out that the Avengers successfully saved the world. Hell, if he were going for something more distinctly Stark-esque, he might ask her for a thank you, seeing as they managed to save 99.99% of the people on the planet including everybody else she knew.
• In Ant-Man’s first movie, he gets arrested for an idealistic/altruistic crime and it costs him his family. His ex-wife was quite pissed that he wasn’t able to support their daughter while behind bars. When Falcon asks AM for help on an idealistic/altruistic crime, AM helps because… he’s met Falcon before, and is impressed by Captain America. Okay, but isn’t his daughter a bigger deal to him than that? Also, given the circumstances of how he met Falcon before (getting sort of attacked by Falcon in the first AM movie) why would he rush to help Falcon when Falcon needs it?)

• Spider-Man’s motivation for joining Tony’s team against Captain America is exceptionally weak. Okay, he’s a high schooler impressed by Tony Stark’s star-power. Okay, but he’s also a New Yorker that was alive when Captain America helped defeat an alien invasion of NY in Avengers 1, and also when Captain America helped save the world in Avengers 2. And, also, Peter Parker might plausibly have been on the Hydra kill-list aborted by Captain America in Winter Soldier. It probably would have helped giving SM some bigger reason to want to get involved than just idolizing Tony Stark. Maybe Tony convinces Spider-Man that they’re only really interested in arresting superpowered hitman Bucky, and that they need to subdue anyone interfering as cleanly as possible. Spider-Man is much better qualified for a nonlethal takedown than almost anyone else Tony could have asked (e.g. compare to Hulk, Thor, War Machine, etc). “Hey, you probably aren’t very excited about fighting Captain America – I doubt any New Yorker would be – but you’re our best chance of arresting a super-assassin without any Avengers getting seriously hurt. You in?” I think this would have helped SM look a lot less flaky/childish than he actually did.
• Secondarily: Vision unintentionally shooting War Machine. I see two main possibilities. One is that an android just happened to miss a shot that badly because the writers needed him to miss, which would be helluva lazy writing. I feel the only plausible in-story explanation is if Vision meant to hit WM (possibly because of mind control, maybe from Thanos’ influence over the gem), which would probably be much more interesting than “I lost focus.”
• Maybe Captain America interfering with attempts to arrest Bucky? He doesn’t appear to consider any alternatives “let Bucky be arrested” and “defeat anyone attempting to arrest Bucky”. E.g. spending a line or two talking with Wanda and/or Vision about whether it’d be possible for them to remove Bucky’s mind control?
• I like the villain’s goal, but it all hinges on Captain America being so fanatically loyal to Bucky that framing Bucky for another murder will create a lethal confrontation between Captain America and other Avengers. Given that this didn’t happen after Bucky committed actual murders in Winter Soldier, that seems unlikely.

3. Out of all the people that could really benefit from financial assistance, the MIT student body is probably pretty low on the list.

4. The cast was probably unnecessarily large. Hawkeye, definitely unnecessary. Black Panther, more on him later. This version of Spider-Man was not written well enough to earn his time/space in the movie. Wanda, arguable. Falcon, probably.

5. The writing for Spider-Man was sort of an odd choice. E.g. bending over backwards to make him annoying, and emasculating him with the scene where Iron-Man pulls him out of the fight. (Over the last 60 superhero movies I’ve seen, when a superhero gets taken out of a fight, typically he either gets knocked unconscious or his combatants withdraw or maybe he faces superior odds and withdraws himself). I don’t think I’ve ever seen a superhero movie (and definitely not a Marvel one) where it looked like the writers hated a protagonist this badly. (If you REALLY want to get into the fever swamps of badness, check out the 1990s TMNT in Turtles Forever). If this was the best they could do with the character, why work him into a movie that already has 10 superheroes in it?

6. Waukanda felt goofy. It’s not the first time a fictional country has been introduced into the MCU (Sokovia in Avengers 2 was a fairly generic setting that mainly showed up to get blown up, and blowing up an actual country might have been too dark). The mix of Waukanda’s 19th century government (king as actual head of state) and very advanced technology might have felt less goofy if it had been established in a separate Black Panther movie rather than in an ensemble movie. Also, I think Thor/Asgard has already covered a lot of this ground, but Thor actually has the fantasy background to make it work.

6.1. Black Panther is a martial artist, a billionaire heir, randomly a jet pilot, and driven to revenge by the murder of a parent. Even before we get to costume design, we’re pretty deep into “Batman ripoff” territory here. Oh, yeah, and he looks like this.

6.2. Unfortunately, they didn’t rip off the stellar lines that Batman typically gets, and personality and character development were sort of missing. With so many characters fighting for time, this probably wasn’t the best opportunity to introduce him. I hope his standalone movie in 2018 will be much better.

7. Tony Stark’s creative contributions have been waning over time.  I think he had maybe 3 very clever lines in the movie. This weariness doesn’t seem to help him very much.

8. Ant-Man was probably the MVP of the movie in terms of personality and writing, though his role was a very small one. Also, I had previously been skeptical that his powers would allow him to contribute much in combat in a superhero ensemble movie, but he actually contributed more to the fight scenes than most of the other characters.

9. Bucky is hard to care about – he’s less of a character than a mind-control plot device to be fought over. I think Manchurian Candidate, Jessica Jones, and even the pilot episode of Alphas handled mind-control much more effectively, generally from the victim’s perspective. Here’s the introductory scene of Manchurian Candidate.