Rule 1: No arguing! Its OK to debate but I don't want to listen to it. The consequences of this will be losing your ability to post for 24 hours.
Rule 2: If you want to make other plans for the group make sure the group doesn't already have plans and make them 1-2 weeks in advance! The consequences of you not doing this will be the sheer stupidity of doing your plans by yourself. Thats punishment enough!