Great game, I love the upgrade system being a bit of a "bet" on the wheel, with options for scaling or immediate rewards. Very addicting despite the simplicity!
One thing I noticed though is that when the enemy spins the wheel, if they land on money, it procs as if the player landed on it and increases your money amount. I'm not sure if this is intended, as this behavior is not consistent with other spots on the wheel. Other than that, the wheel game mechanic seem very intuitive and fun!