Here is a demo of some piano music. There are three movements:

1) Upbeat piano > 26 sec.

2) Sad piano > 1:52

3) Uplifting Piano Rock
from 1:52 on

I can put some other melodic elements & more percussion, etc....
to make more variation. I would put a bass in the Piano rock part, also. I don't want to get too far ahead, until I know if I'm on the right track.