It's basically the story of Wolverine and a number of other vigilante movies. You can only go so long with a hero doing things wrong because of his rank; it's just not a conflict that most people will sympathize with.

The problem with Iron Man 2 was that Stark wasn't really all that self-destructive. Nothing he did really ended up hurting him; in fact, if he hadn't gotten piss drunk, Rhodey never would have taken the suit and been able to fight with him at the end. If Stark's stunt at the race track ended up killing innocent people and that began the downward spiral, then it might have been more interesting. But instead of adding depth to the character, Act 2 was the prologue to The Avengers.

As it was written, the Iron Man character was typical. But there's more to do with the character. The War Machine angle would set-up a different first act but then it's just like Iron Man.