All fair points. I was balancing the game out after basically a day of continuous devving lol, so the stuff I decided to implement last minute like difficulty scaling over time was a bit busted. Originally, the enemies would spawn at closer to the rates you see at the start of the game and nothing else, so that influenced their hp pool quite a bit.
A lot of the dissonant art stuff you see in the game is the result of overreliance on in-engine colouring and image blending over adherence to the palette due to trying to make everything look alright while being pressed for time
As regards clarity of the upgrade buying option I was so mushbrained at the end of it of it all that I was going to implement a simple "-(number of petals you lost)" draw call whenever you picked it up, but I was just too exhausted