For Iron Man 2, my only problem was Whiplash. He sucked, both when it comes to writing and acting. Besides that, I liked it. I liked all the SHIELD stuff, and the introduction of the Black Widow. I am really glad we never got too much of drunk Tony. The drunk Tony scene in IM2 is the most problematic, anyway (seriously, can just anyone steal his armor? He doesn't have it tied to his life signs, or even just password protected?). It wasn't bad as a comic storyline, but "Demon in a Bottle" is not a storyline I think ever needs to be done in live action. One thing Marvel has definitely been great at is mixing serious stuff with not serious stuff. Having some involved plot in a movie about Tony Stark's fall into alcoholism would be way too dark, more like a Nolan movie. With a better villain, I think Iron Man 2 would be great, instead of just very good.