How much should we edit? I see the value in the ability to improve questions and answers made by other users, but I also believe editing has some downsides to it.
Do we scare newcomers away? Asking the first question can be difficult. One might not know what language is suiting in this kind of forum. Having your question edited, your original text turning up all red on your screen isn't very encouraging. Small things as removing greetings, changing titles and removing tags such as "grammar", are they really necessary? I think we lose more than we gain here.
Why edit back and forth? There are things we all have different opinions on. And instead of editing back and forth, we should discuss what should be allowed and not, in the meta. Whether or not "in Esperanto" should be allowed in titles is a such example. Another is about the above mentioned "grammar"-tag. We should vote about what we want. If the outcome is that it doesn't matter, if these things appear in posts, they shouldn't be removed through editing.
Of course there are things that are simply wrong. I'm not saying we should stop editing. Also, we can't vote about everything. But rearding the most common edits, I think we should come to an agreement.