I really like the taging of other people as well as governing bodies, some sort of mods that at least challenge upvoted and posts from users that appear to have a spammy behaviour as well as monitor downvotes. I don't know how much the latter would be needed if this existed. Tags could be possible on a third party website using the api, but than you would need a small community of devoted people from the start otherwise there won't be anything to gain in the eyes of people that aren't part of it.