Im a nut for classical/piano pieces. The first thing I realized is that the piano was sequenced instead of recorded live; you can add realism to piano by affecting velocity to each note. Because realistically, someone doesn't play each note with the same amount of power! (Google velocity tutorials if my comment confuses you haha)
Besides that, this piece is really awesome. I'm not sure if you're wanting anything more than Piano, but adding strings or guitar might make this even BETTER. Just a suggestion, keep up the great work OP :)