If you do make it into a full game, here are a few ideas:
- Don't introduce all the power ups early in the game, keep em spaced out to keep the game fresh.
- Maybe pull a Metroid Prime moment where you give the player amazing power then suddenly take it away at the beginning.
- Co op would be a great addition.
- Maybe make it a Gauntlet clone? I don't know if you've played Gauntlet.
That's all. See ya!