Fun game, thanks for sharing it. I agree with an earlier comment about visibility maybe suffering from almost everything being 1 color.
I wonder how things would look if enemy aiming lines and spawn indicators were a different color & drawn on top of bullets (maybe some kind of transparency on spawns to be subdued). Star items being yellow is nice & all but they're not a danger to your run ending in 1 mistake lol.
If there's a later version I'd appreciate support for controller + mouse simultaneous use. Currently if you do a gamepad input it stops reading the mouse and you cannot aim (instead reading the right analog stick position even when it's in 0,0?)*
I got a 1 billion score and felt the threat introduced by 99% of bullets after they entered the field was not running into you but that they are blocking visibility for upcoming threats.
For example enemies that ram into you spawning under a cluster of bullets is far more dangerous than the bullets. The line indicator and where they're spawning is blocked.
It's a common rule in shooters to draw bullets on top of every other sprite for max visibility, but since they're less dangerous than average maybe it'd actually be better to draw some things over the bullets. Since they can be shot down before they ram into you they're kinda leaning towards missiles/zako/popcorn enemies in other twinstick shooters.
*Full gamepad control felt totally fine with the shotgun. I could see mouse aim being comfy with precision weapons or someone trying to really optimize bullet cancels with manual fire to not shoot bullets (if the game goes on forever this is probably pointless..?)