So as of right now, the vast majority of singlename/singlename relationships and singlename characters should be cleaned up, as long as there were more than 3 uses. For instance, there were 34 stories out there with the tag "Oz/Xander", and that tag still exists on those stories. However, when you click on the "Oz/Xander" tag, it redirects you to the tag "Alexander "Xander" Harris/Daniel "Oz" Osbourne [Buffy the Vampire Slayer]" and all stories that were under Oz/Xander now exist under the parent tag. There were at least a dozen different "Xander" type characters out there, when in fact there should be two - Alexander "Xander" Harris and Xander "Triple X" Cage. So now most of the disparate "Xander" characters should all roll up to a single character for that fandom.
This cleanup was massive - but at least this wave of it is done.
There will continue to be cleanup as time goes on, because the database needs to be tidier than it exists today. This shouldn't mean anything to folks using the archive - just keep doing what you're doing, and that includes adding new fandoms, characters, relationships, and free-form tags as you need. If you're curious as to what we are using as guidelines, you can always check out the Wrangling Guidelines for SquidgeWorld.