maybe we could come up with a tag that excludes all tags except for tagme, then it'd be easy to find images that are only tagged with tagme.
Or come up with tags that define posts that only have so many tags. for example if we called it tags:5 the same way we use score:5, then it'd find posts only have 5 tags
I don't know anything about coding, so I don't know if that's possible, but if it's not then could we have a tags:n that automatically updates itself by adding up the number of tags a post has
It's also a little bit of a problem when we come up with new tags, we tag new posts, but no one bothers to go back and tag the older ones. Maybe if we could be allowed to use more tags for making it easier to go back to older posts. In Pokemon for example, we have this no_humans tag that has pictures with only pokemon in them. It was added recently, so almost all of the older posts didn't have it, I went back and added it to the ones that needed it. I searched pokemon and excluded the most commonly appearing human characters to minimize the number of posts I had to go through, it would've been nice to have been able to exclude one or two more humans. Also that reminds me that I also added the nyoibo tag (for son_goku's staff), that one has been taken care of also. BUT the thing is that that tag had been forgotten, I only noticed after posting a picture with the staff in it. I think someone else might've noticed that it was missing, and maybe they knew it had a name, but didn't remember it was nyoibo, so they didn't do anything and/or felt it'd be innapropiate to post in the forums "just" for that (since a lot of member don't know it they can).
We could have a thread listing all the tags that need to be added to older posts, etc. Where people can report a tags that need to be taken care of. Then whoever wants to can just go back and add them.