I'm thinking the group will have similar history to it's inspiration: the justice league. After working together on a few things, these guys just got together and said "Fuck it, let's make a team."

Have not decided on the city. Thinking something cliche like New York or some other large city. 

The villains depend on what you guys come up with.

Time period is current. However, superheroes have always tended to own more advanced technology than their time period allowed. That's fine with me.