2) Delete the rankings given by any person who has been banned from a given Agoracom Forum in which they have been active.

this is already the case. when you ban one of the bashers, the 1-star ratings they gave out disappear. that gives us some incentive to throw out the bad guys. and when you ban someone, it is from all of agoracom, not just the forum where they were causing trouble.

agoracom can tell exactly who gave what ratings to whom.