Have teams either picked on their own or like a school yard pick. Have different divisions, each with increasing buyin. Could basically use the point system grinder promo uses, just goes to the teams overall points.
For instance, have a 2 week league, and every game a person is picked by captain to be double pt winner, but a person can only be doublepts twice in the two weeks.

and obviously the winning team gets prizepool of the entry fee