I did a quick read of the thread, and I don't think this has been mentioned yet.. I think by far the fairest way is this:
Keep track of how many points you kill on the other two teams. Your final score is the
lowest. So if you kill 350 on one team, 75 on the other, that 75 points is your score. It makes it's so that you have to focus on two different teams instead of the same one.
Unless your my brother. In which case, you will happily take the loss if it means wiping me from the board
