Thanks for the detailed review!
The health as a penalty for lack of coins idea is super cool, thanks for the idea!
As for the cause of the lag, you guessed correct, that is indeed the cause. I'd have loved to optimize it more if time allowed, but this was my first time in a game which actually used a lot of shaders, so I was unaware of these issues before it was too late :(
Thanks for the review and help though! I'll definitely create a more generalised solution to use in my future games for this kind of stuff :)
Thanks for playing!