I would have to say Tony Stark. Overall he reminds me a lot of myself. The man is arguably one of the most gifted minds in the Marvel universe, and yet he is driven by an almost (sometimes) construed sense of justice. He has conviction and is willing to do what he thinks is right even if it breaks the rules. At the same time, when things don't go his way, he takes it in stride and fixes the problem. The man is a hero who spent the better part of his life as a playboy. But under the circumstances presented to him, he changed his way of thinking with the thought that the world didn't need weapons if he could build the one weapon the whole world would come to fear. In the end, I don't feel he was concerned with being the hero or the villain; it was about doing what he thought was right regardless of what anyone else thought. He wasn't about to stand down or be bullied, which I find admirable in a character.
The man is smart, witty, and most of all dangerous. Not to mention that while he likes to brag and come off as egotistical or even selfish, he has proven that he is willing to potentially sacrifice himself if it means saving the world. He can make those tough choices that no one else can or will and take the burden of living with them.
~M