Epic game!
I would love to make it better, but I'm sadly not a good coder.
Just a few little things I would fix.
Coins are too small, so I would make them bigger.
Dashing sometimes doesn't work, so I would fix that.
I would also add a miniboss at floor 5 and final boss at 10.
Last things: New power ups like a shield heart, it adds to your health.
One thing that would be super dope is a deflector that deflects bullets.