I agree with you that this needs to be self-enforcing, and yeah, the only way to do that is to have a list. We’ll start one over the weekend and I’ll amend the rules accordingly. Yes, it will be short. As for your first point, that would be tough to enforce. If a post consists in its entirety of, “You’re an idiot,” some will think that violates the rule.
One thing I’ll think we’ll put in the rules is something about “exceptionally vicious, hateful, or shocking remarks.” One of those things you’d invoke maybe once a year.