Hmmm, finally completed the game and it's actually quite fun. I do like the whole gameplay loop, and with a bit more polish and fine tuning, it can really become something remarkable. Probably some auto platformer like Runner or similar games.
There are a few places where the game can quickly improve on, so I'll go one by one. The most significant one is the short time-pause effect when defecting the bullet. Although it's very cool, the game doesn't not start directly from the pause, but rather skip a few frames after the pause is done. This results in a very unfair feeling of not knowing if I am turning correctly until I am dead/alive. (Notice I am not complaining about the mouse rotation thingy here). I would say just a simple fix of a true "pause" (a bit shorter too) and allows the player to react and rotate before the next bullet spawned would be a huge win.
The second one is the lack of UI especially during death. Some screen of saying "You died, press R to restart" would be a very nice addition to the game.
Some other minor issues such as the human enemy lingered too long on the weapon, lack of UI to show what to press (preferable some image with 1 = shield, 2 = knife, 3 = arrow), etc I will not elaborate too much as they are just polish at this point.
Anyway, I see you put a ton of effort to the game and I hope you keep on developing games. Keep on the good work!