Thank you for the feedback, I really appreciate it!
Yeah I can definitely agree it's hard to tell if the enemies hit you. I wanted to do a slight vignette effect with a screenshake with robot buzzing but lost time. I am working on that right now actually as that was something mentioned before! I will also adjust the difficulty of the waves a tad as well.
Actually yeah there is a better jump powerup! It's somewhere in the pool of upgrades. That being said though I agree the base jump is still not high enough. I will adjust the number for that in the next update and probably adjust how its coded as the way gravity works makes the character fall way too fast.
I am glad you think it's interesting! I was not able to get the art for baby skill trees inside the game, but by upgrading the enemies better power ups would start appearing in the pool that were stronger but come with a catch similar to Binding of Isaac's Devil deal system. I am playing around with it still, but introduced it early to see the reaction. After I polish off and adjust a few powerups I am hoping it work better with the system.