I have to say, really good and solid game actually!
It can get definitely further improved on and extended to create it's own story (specially since we get to see one more creature on the side that I want to know more of)
I think as an interesting way to make it interesting, would be to have a sort of "infinite" or freeplay at some point of it to serve as a way to practice or get new high scores, but up to ya :P