One word: Mjollnir!

Rating: 9/10 (1 May 2015)

I have noticed a trend of negative reviews directed at the humor in the movie. Listen...humor is subjective. It's also a big part of these types of movies. When I read someone criticize the movie because the heroes are dropping one-liners during intense fighting scenes and to them, this downplays the seriousness of the situation or shows a lack of concern for safety from our heroes, I shake my head so hard I get dizzy.
This is a comic book movie! It's a fantasy/fiction/whatever you want to call it! I'm not a comic book expert, but have been a big fan of the Marvel Universe on film since Iron Man 1. I found the writing in AoU to be sharp and witty. And yes, I laughed more than I thought I would.
"There's not enough character development!" I've seen this in the negative reviews, too. Look, we've had 3 Iron Mans, 2 Captain Americas, 2 Thors, and a Hulk movie to develop the characters. At this point, there isn't much more we really need, is there? Yes, we see more about Hawkeye's personal side here, but to me, that only feels fair since he's not big enough to carry his own film. And given that he's very much just a human with a great set of physical skills and is less protected and faces his mortality far more than the others do, I felt like it made perfect sense here. We see and learn more about Black Widow in this one, as well. So the complaints about character development don't hold any weight to me. It sounds like the angst of a group of people expecting to see the Empire Strikes Back version of the Avengers.
In Age of Ultron, we get immediate, sustained action. I don't know about you, but if I'm going to watch a movie with a cast of characters that have the abilities of the Avengers, I want to see them in action! The creativity of the collaborative fighting was improved as well and was featured much more so than in the first one. That was something that I think the first film lacked, the side by side teamwork. This movie held my attention from start to finish.
As my summary says above, Mjollnir is a pleasantly surprising star of the movie. When you watch it, you'll see why and in my opinion, if you don't enjoy its role here, you really just have a bad attitude!