As for the Action/Big Explosions that's more due to what movies has become and bringing in a bigger audience. Avengers, Dark Knight, Hunger Games, Skyfall, Hobbit were the top 5 movies last year and I think it's safe to say Action and Big Explosions were are big part of it. However, there is talk of doing another tv series where they can focus less on that though.
Edit: Here is the link to the Disney Theatre Iron Man 3 dispute: http://www.deadline.com/2013/04/iron...e-with-disney/
It's kind of crazy to think it's even possible IM3 won't be showing in some theatres.