Cool concept, I think you definitely overdid it with the screenshake though. Which is a shame because I really liked the stark contrast between the shooting and non shooting modes, and some amount of screenshake is certainly good for that! But this amount was not great from a visual experience and did not make it super easy to aim.
I also think that the enemies take way too many hits to take down, even if they get slowed down while shooting.
But the overall aesthetic was really well done, and definitely close to being great =)