It's definitely got good ideas to expand on further, though the gameplay might be a little too easy, and it seems like there may have been things happening on the left that were not obvious, at least to me. I do kind of like the aesthetic you went for, and the main menu and splash art is nice, though the gameplay art and score display could use some more. Overall good submission, and if you plan on doing anything with this it would be nice to see where it goes.