Hi,
excellent concept, congrats!!!
I would create a smoother input control for a better visual experience rolling smoothly basically.
ideas:
-- go for multi users, so that you need to be two or more to complet or compete
-- basically get inspired from other games to know what kind of more complex level you can do
-- let the user control more rotating elements
-- Are you planning on mobile distribution, this would be a very good game to use the gyroscope!
bye,
Jean