Thought I'd mention that this whole discussion has led me to looking at ways of doing something similar with my own library. For instance, I created an auto-playlist of "local artists" using the "Album Artist is any of" rule. But that always leaves me kind of nervous that if the playlist is messed up somehow, I'll have to do all the work of remembering which artists should be in it again, which may also be a concern in your case.
But I've had a custom tag for a long time called "Playlist Filters" (actually, I had multiple custom tags for different types of playlists but I was running out of room so I folded them all into one), and I think I'll just expand the scope of that. So instead of a rule of "Album Artist is any of..." I'll tag them with a playlist filter of "local" and make the rule "Playlist Filter is local".
Just something for you to think about, because it would make it easier to reconstruct the filters and playlists if necessary.