Nice! I think with the limited shapes constraint, colour is actually really important and the colours in your game are quite harsh - you want a little bit less contrast, and less saturation. I find that picking one colour and using https://mycolor.space can really help with that!
The gameplay is surprisingly well balanced for having only two input methods - I like the upgrades and I like that I don't have much control over the character but it is still possible to avoid things. There's a nice "easy to learn, difficult to master" type flow here - well done.