My chapter's system for informal works pretty well, but I can't really go into detail about what we do, because membership selection is the private business of my chapter. This would be a good question to ask an advisor or a traveling consultant.
I don't think anyone is going to answer you as this is treading a little too close to private membership selection practices.
But I will say that I'd be pissed too if 3 people were going out and bidding who they wanted without anyone else's input. ("Input" is not necessarily official votes.)
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It is all 33girl's fault. ~DrPhil