I think adding more freestyle categories would be fun. For example, a fun meme category could be fastest to out of bounds zone. Also when I was younger me and my friends would try to get into the hot air balloon basket without dying in the wells level. I think level specific challenges would be fun like fastest to get into balloon basket or fastest to backflip into basket. I don't know about the other levels maybe somebody else has a suggestion. J just think the freestyle mode is the best category for this game and more challenges would be great.
I think this is a nice idea, but the community for this game is so small that splitting it up even further will likely kill off any chances of it growing in the future. There is the appeal to more things to tryout but I am personally much more interested in the competitive scene more than anything.