Now, let me answer this as shortly as I can without becoming too self-indulged (it will still be a long post regardless).
You definitely should not put me in a box, because you can't, because I'm willing to bet that I, by far, have the most expansive (broad) taste on this board. That's not a brag or a boast, it's just a simple statement to emphasize that I am a man of many, many interests, and there really is no extent to the things you might find me liking (or disliking).
Onward to this movie,
let's start by saying it's a movie that knows what it is. It is a superhero team-up blockbuster and all of it reflects it. Whedon, for what it's worth, understands the core principle of what makes a superhero a superhero, and in case it isn't clear, let me give a hint, it ain't the powers. Superheroes were created as our imaginary protectors in a world in which nothing will protect us, people who accomplish and live out the ideals that we strive for and give us something we can look up to. In short, it's the person that makes the hero. There's many things you can fault the Avengers movies for (or Marvel movies in general), but they never lose sight of that, and always make the movies about the hero(es). So much even that often (too often I'd say, but that's a different discussion) the villain is just a placeholder, a stone for the hero to step over in his journey. Then again, Indiana Jones gave us three classic blockbuster movies without a single memorable villain, unless you want to count the guy from the second movie even though the only noteworthy thing he did was rip a heart out (probably the sole reason you're thinking of him now), or the hot Nazi chick from the third who you damn well know you only remember because she's a hot Nazi chick (if you google "nazi chick i" it automatically suggests "hot nazi chick from indiana jones and the last crusade" for a reason).
Anyway, in this case we get (for the most part) spot-on characterizations of multiple superheroes, each with their own character arc (no matter how small) to explain why they're fighting and what for. Cap is simply a good guy who will always fight for what's right (while searching for a place called home in a world still strange to him), whereas Tony went from self-protection to feeling the need to shoulder the weight of the world (to a fault). Widow tries to atone for her past sins, whereas Thor has the power and thus feels the responsibility to protect the entire realm. Banner doesn't want to fight but knows the Hulk is a necessity (much to his own dismay), and Hawkeye is a dedicated soldier just trying to protect his home. No, they're not baffling groundbreaking motivations, but in both Avengers movies Whedon finds ways to expand on each and every one of them, make it seem like they actually add something to the movie (compare that to say the arbitrary named and colored Autobots/Decepticons in the Transformers movies) and bring them to life in ways even some of the solo movies can't pull off (looking at you Thor movies, as well as what a generic motivation-less wise-cracking hero they made Star-Lord into, and what a generic motivation-less wise-cracking hero Scott Lang is looking to be shaping up as right now).
Then there's the action, which delivers tenfold. The action builds naturally, each set piece consistently has stand-out moments and utilizes every character's unique abilities in different ways. All in all, to keep this thing short, as far as action goes Whedon knows what he's doing. And luckily for us, he actually stepped his game up as a director as well (thank the heavens for that btw) so this movie for a change doesn't have the aesthetic look of a tv-production. Seeing as that was my biggest issue with the original movie (which already got the things right that I talked above), huge improvement.
So we got a superhero team-up blockbuster that delivers on all aspects of a superhero team-up blockbuster, so I should dislike it why? Because it can be a bit too jokey, to the point where it seems as Whedon wrote this he put in little in-jokes for fun, and because nobody bothered to check his ass he actually ended up putting all of them in the movie? Because the soundtrack is so lackluster you only ever notice it when there's a scene that really feels like it could've used a better soundtrack? Because I don't like the idea of Banner/Romanoff hooking up, even though you really can't fault the way it's written (and I'm a writer at heart). Because the story is so chock full of developments (mostly to push upcoming movies) that sometimes they dedicate a single line of dialogue to a development and expect you to roll with it? Because the good guys win without too much sacrifice, and the villain's six-hundred deep army couldn't touch them, like they do in all these movies? Because it doesn't try to be more than what it is? All of that is minor stuff in the face of what it does right, and therefore, forgiveable.
So if you wonder why I give this movie more slack than 'other' movies (blockbusters? 'prestige' movies?) it's because I look at every movie for what it is and aspires to be, and this movie knows what it is and accomplishes what it aspires to be. Whereas many, many movies, simply don't. Just because Nolan makes 'deeper', more grown up high-brow blockbusters (or at least, pretends to, because you know how I feel about that), doesn't mean they're automatically better blockbusters. And just because Innaritu can copy/paste twenty tracking shots of pretentious self-conscious monologues/dialogues together, doesn't mean it automatically makes better cinema than a movie where Keanu Reeves' dog is killed and as payback he murders the entire Russian mafia. Because if you look at the movie that John Wick wants to be, and the movie that Birdman wants to be, I can say without as much as a doubt in my mind that only John Wick succeeds, and as such, shyts all over Birdman. And just because Birdman sets its goals higher, doesn't mean it gets a pass. Because I don't judge movies for their aspirations, I judge them for what they end up being. And that's why you can replace John Wick with The Man With The Iron Fists 2, or even the WWE-studio DTV movie The Marine 4: Home Target, and Birdman would still lose. Because that movie simply doesn't work for what it is.
