I'd ABSOLUTELY say no edits. 

I think it's part of the ethos of Nostr--and a reminder that Nostr is different--it's about privacy, and freedom of speech. No edits are a part of that--

Just like in real life--once you say something, you don't get to pull it back. Yes, you can apologize but your words are forever.

So it is with Nostr.

Think before you speak--both IRL and on Nostr.