I have an idea for a copy of your post to be made before an edit goes through.. Like say I post AAA And then I edit it so it's now AAB, maybe keep a copy of AAA in case I didn't want it to be AAB. It doesn't have to make a copy of every change, maybe just the most recent version before an edit or the original post. An option could be made for it in your preferences, as well as letting other people see past edits or not in general or for a specific post.
I'm asking after I accidentally wrote my new post for an RP over an old one by accident. I don't know how to get back that old post so it's now this weird out of date post before the events that caused it to occur. Basically it's out of chronological order, which is.. Eh. Still think the idea would be good irregardless.
If it's a matter of storing them taking up space you could have it so that the copies of the posts get deleted after a certain amount of time.