Multi-Sport & Editing privileges
Either create a shared link between all sports for a multi-sport set or create a Multi-sport section for card sets, or have better moderators reviewing user entries. As is, the 1992 Classic Four Sport, Draft Pick Collection is scattered between every sport it covers. Users have added football numbered cards to the basketball section, etc. The last one would help the site the most, because user entries could use a little more reviewing before posting.
Another solution to user changes or edits could be to have community reviews. People could go in and view recent edits and do some sort of +1 such as the thumbs up. Once it reaches a certain number of supports, it could go live. Might be a way to offload some of the review work for admins.