This could get fun
Just an idea: For the game to be enjoyable the tracks/levels have to be good. Maybe it would be better to separate a level (track) editor and the game itself. People could create tracks to their likings then - which could be a manual or half-automatic process. I guess I'd even prefer manual if it's easy to use - which in turn, also would mean one problem less to solve for the coder.
For example stepmania, which is a pc freeware dance-dance-revolution clone has a level-editor. And it makes perfect sense.
Action in the video starts at 4:30
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