How about a gambling den? Bitter ex-superheroes try to constantly cheat each other at cards, using all their superpowers to achieve it? Let's see, it could give us the recurring characters of a small bunch of heroes, the barkeep/owner, and the bully guard. We could have the character of the guy who always wins in spite of never ever showing any powers, the x-ray vision guy who drinks too much and ogles women? The speedster who runs around changing cards... I see a lot of potential. Where should we sell the idea?