I like how the risk factor is! You are actually, truly rewarded well by risking and going for the low percentages.
If you go for high chances often, then more than likely a few rounds in, you can't afford the upgrades <-- I like this because it incentivizes the player to go big or go home (risk it for the biscuit). Its truly within theme!
The song choice is very catchy as well. I could listen to it all day!
Great job!