//EDIT: Just saw that B$ are banana bucks. How do people get these and what happens when they "cash out?" I watched your "intro" video [which wasnt very prominent on your homepage] and still dont really have answers to most of the questions I raised
As far as the legality, I really wouldnt be so sure about your 3 prong test, ESPECIALLY if you dont have a lot of money to fight the DOJ. Will they come after you? Depends on how big you get and how well you hide, but if they do come after you, you cant just say "Sorry, we thought it was legal" and shutdown the site and expect them to stop going after you.
When you say, "Furthermore users can’t wager or bet on teams, they simply pick which team they support in a match." What does this mean? Why would a user "pick" a team? What happens if they pick a team and that team wins? What happens if they pick a team and that team loses?