What are/have other leagues tried for bonus points?
The whole idea is a little odd to me, though I get it's to underscore the social aspect and give the social/weaker players something to get excited about. For our current league, I came up with the idea to do it based on total group score - kinda make for a group goal. Highest sum of scores for the night gets one bonus, lowest gets two. It's a pretty solid idea if you come up with a way to balance the group games scoring wise, but it's a PITA to do all that math, so looking for other ideas.