I made it through and beat a story level, a few challenges and the shield boss hard mode, both encounters took 3-4 attempts. At first I disliked the bullet hell aspect but I can get used to it. It's just too prominent in the first level where you barely even get to shoot enemies at first (which is more satisfying than squeezing between). That said shield boss should have more attack telegraphing because the bullet hell segment has too much stuff happening and it's hard to react to fast pink projectiles when you are tangled in avoiding other projectiles. Same could be said for all other enemies if you are planning to make it bullet hell heavy.
I like the crushers because of the neat pathing you designed in the challenge. I got a weird bug where I somehow squeezed past horizontal one by clipping into the floor and then popping back out. That reminds me why I'm not using box2d and the likes.
I like that you left the recoil in but I'm still not sure about the gradual falling down without strafing key as I don't understand what purpose it serves.
Subweapons need better icons to be recognizable at a glance. Axe feels disappointing when it only hits once.
I need more story levels as the one segment I kinda liked isn't there anymore.