Add music training capability
Musescore is now a first-class score editor and offer much more than what an average music school is waiting for in term of score editing and printing.
What could be a future goal is to embed some music training function. My idea is to add something like Jalmus does (http://www.jalmus.net) but with all the stability and functionality offered by Musescore.
I believe that most of the pieces to build this puzzle are already in place, and it would greatly benefit to music students regardless the OS they use.