It would be great if a user could delete their own post, but instead of it being removed, it was moved to a trash bin, in case the need arises to track a trouble maker and retain proof.
That would be easy to implement, wouldn't it?. Instead of sending the posts off into Never NeverLand, just have the routine send them to a table that you've created for trash instead. (w3t_Recycle) You could browse through it as an admin and even have a cron set to purge occasionaly if you so wished.