He might develop a greater sense of humility. Without the Batman persona to fall back on, he has to face his own limitations as a person. For example, he may struggle to get people to listen to his ideas for change when he doesn't have the intimidation factor of Batman.
Sure. In the comics, Bruce Wayne is known for being a playboy. This fa莽ade allows him to blend in with high society while secretly fighting crime as Batman.
It depends on your perspective. Some might view Dr. Manhattan as a villain because of the way his powers and choices impact the story and other characters. But others might see him as more of an anti-hero or a morally ambiguous figure.
It's a matter of debate. Some might argue there are other characters with equally or more powerful abilities. But Dr Manhattan's powers are indeed incredibly vast and might put him at the top for many.
Another aspect could be that in some darker fanfics, if Bruce Wayne were to cross a moral line, perhaps Alfred would have to take more extreme measures. He might cut off Bruce's financial resources related to his vigilante activities. This would force Bruce to re - evaluate his actions and the way he operates as Batman. It's a way of punishing him to make him understand the importance of ethics even in his fight against crime.