Nice, I like this one! The weirdness of space physics is fun!
I stumbled over it because was looking at games from the 4MB game jam, since I might participate in the next one.
(I'm fully aware that there is almost no chance you will ever work on this game again) I think the most high impact low hanging fruits for the game would be
- High score and some positive feedback after death about beating the score (bonus for online leaderboards, but that's more work)
- Music