All you have to do is something cool. Stop stupid shit that would be "Superman simulator" and allow the player to pummel the shit out of big bad guys. No one wants to constantly put a falling building down gently, or fly around trying to pick up civilians, or to escort someone, or to beat up street level thugs. They just want to fly around, put the big bads through skyscrapers stopping their world ending plans.

Anything beyond that is lame and gay. Even something as "unstoppable" as the Hulk got scaled down in Ultimate Destruction and let the rule of cool take foot to run up buildings, toss cars, and jumping on helicopters to bring them down. Just be fun.