I played the game and it was really nice. I also realized that the levels and enemies were auto generated from a few set of floors. That means probably no of ememies and ememy type are determined at runtime using code.
Seems like the no of enemies per floor looks a bit too cluttered? I mean on the floors with larger space having more enemies is cool with rising difficulty. But on smaller sized floors having a lot of enemies fills the screen so much so it becomes hard to distinguish between a Tank and an Aero Shooter. Most of them have the same color probably trying to implement the same aesthetic but makes hard to distinguish between them until you are shot dead.