Mod99 – Makes sense, and thanks for the explanation. Since you already allow editing within 5 minutes, even if the post was approved earlier than the end of the edit time, the concerns you stated above would apply in that timeframe.
I suppose you could “test” how things work out by increasing it slightly, to say 15 or 30 minutes, and see if it is abused. If so, you can revert; if not its great. Just a suggestion.
BTW, during the several weeks posts were going up immediately unmoderated, I believe there was only one abuser. The benefit of that system was that conversations were much easier. Obviously even with only one abuser you still need to rectify the situation, but with proper vigilance perhaps you could be a bit lenient and see if the situation allows such leniency to continue.
Good Shabbos