Very original game - a great experiment, which definitely made me say "Wow"! But... My brain hurts :D It's almost like playing Overcooked alone with 2 characters :D The aiming while rotating is already hard enough, but managing both characters is a bit over the edge for me... But that would be a totally cool 2-player game! I could easily imagine playing it with my gf, and shouting at each other for missing a ball :D
I also think the circle should be a bit larger, to have some more room for the ball to travel, to feel less overwhelmed. And some upgrades/progression would be cool if you decide to make it a full-fledged game. And I do think it would be even more fun with 2 players! :)
(I played with keyboard though, so maybe with controller it is less extreme :D)