Hmm, I like it, it promotes teams. Maybe if your team wins, you get a better match reward at the end of all the battles, and if you win a match, but your team loses, they could cancel out, and so on.
P.S. Ther could also be clans based on element, but just where a track is kept on which element has the most wins overall.
P.P.S. Would you form a clan for just that match-up, or would it be over a long course.