Originally Posted by Happy Jack
IM2 was not dark enough that's true, but I don't think it would have been necessary for Tony to have hit rock-bottom, unless Favreau and Marvel were planning to do a trilogy. That structure calls for things to go to hell in part two (think Empire Strikes Back and TDK), which in Stark's case would probably mean hitting the bottle. That story beat will probably be explored later, but we know now it won't be in Favreau's hands. That might actually be a good thing, because although he did a good job balancing humor with characterization I don't know if Favs had what it takes to effectively go that dark. I don't know if Marvel can either.
Tony's alcoholism wouldnt've needed to be explored for there to have been some drama. The problem with IM2 was that none of the drama inherent in the story panned out at all. Tony's illness had no effect on his ability to use his suit, for example. Imagine how tense the fight between him and Vanko would've been if Tony'd had to struggle to fly and shoot. Then the symptoms of the illness are just removed by Fury, so there's no excitement in Tony's search for the cure. Again, imagine if he'd been slowly weakening until he discovered the cure at the last second. That would've been interesting.
Then there's he conflict with his dad. We learn that Howard hadn't liked Tony, then we suddenly find out from the video that he did. That subplot wasn't well handled.
That's not even mentioning the fact that Vanko, the most threatening villain, virtually disappears for the second act of the movie, only to be replaced by Hammer, a much more comical villain. It's like Theroux wanted to create such a funny, family-friendly film that he forgot to add any intense drama to it.