Interesting twist on the genre, I like that you really have to focus on catching all the bullets. Simple and yet effective controls.
Due to how the wave works, I was always catching all the bullets, then going round to finish off the monsters. Perhaps it would be cool if the monsters fired at different times, and then you would have to manage killing monsters at the same time as catching bullets, rather than killing them at the end. I also felt that the hitbox could have been a bit bigger too.
Great work though, I had fun!