Just a few more options for shorter challenge mode runs (similar to the single exhibition game runs)
toy field % - complete all minigames + toy field in challenge mode
king bobomb - hit a king bobomb hr as quickly as possible, stop time on fireworks
jr% - beat bowser jr
maybe a collect x coins in toyfield (non-challenge)
just some miscellaneous ideas
All Captain Superstar%:
Marathon of each captain in challenge mode where the only player that needs to be a superstar is the captain of each team.
Would 100% from a new save file be a fun idea? I know we do a lot of stuff in All Superstars, but this would give a couple more challenges/things you'd have to do, and would be a "Full Game 100%". Also might ask to add a category extensions page?