I was thinking that a category could be added. All songs King Crazy on Different difficulties. (4 separate categories for each difficulty) I really love this game and have been playing it for a while. Just a thought

This is honestly one of the only good ways to speedrun this game. It's actually something I did on All Night when the game was relatively new, didn't highlight the stream though. If this does get added I'd argue that support modifiers, other than the one that only increases money gains, should be banned. Challenge modifiers should be fine.

Other potential category could be all black medals.

I would agree. I think the only modifiers allowed would be challenge modifiers, support is banned for sure