Tekniko, thank you so much for the feedback. It's been mostly a one man effort, since my friend helped with some art part-time on and off whenever he had time, whereas I devoted full days (and nights) to it.
The first 3 levels are actually the lowest quality in terms of art, we were learning how to draw starting out (literally pen, paper, youtube tutorials) and our early creations I would say are crap compared to later levels.
I was wondering if that type of gameplay is unique since I haven't encountered many games where the focus is to deflect enemy attacks.