Since the beginning of time...
Humans have competed, for 'POWER!'
But can an entity ever have something such as "Too much power?"
Would we chose power?
But as you come to think about it, he is no longer human but a mere phenomenon that retains some human characteristics such as emotions. Even though he may have the ability to see things he doesn't actually have total control over them. Or as he puts it, "we're all puppets, Laurie. I'm just a puppet who can see things"
The question of having 'god-like' powers is a lot like the philosophical one about whether humans would actually want to be immortal. His power makes him extremely nonchalant and ignorant to the value of human life, the very purpose of life seems to vanish, and in such a situation, would we still assume his power to be desirable? I doubt. Given a choice, I believe Dr. Manhattan would have much rather been Jon Osterman.