Everything is cool except controls. You need to point your mouse with right hand, then you need to use arrows with left hand(or right hand), and then you need to press space with your left pinky(or left thumb), and then repeat it(sometimes you also press Q and R, which are in opposite side of the keyboard), and sometimes if you aren't fast enough, you can accidentally spawn two balls. Sometimes I feel like I am playing piano. I think it's better to use mousewheel to change the size, LMB to spawn balls, and R for restart.
But in general the game is very nice