I don't think there is an "edited by" tag on posts in XenForo (correct me if I am wrong). If this is the case, have you missed having this at all? Is there an edit history - I'm slightly worried about having moderators who can edit at will with no accountability or history of what they have done.
I like to be able to promote sponsors to a new usergroup and give them a nice graphic to show this - but also trade users too - and have both tags showing if they belong to both sets. I think there's an option in vB3 to display usergroup graphics cumulatively. Is there similar in XenForo and if not, I assume it's a simple bit of code that says "if member of usergroup x show graphic y" which you can added to the postbit?