Thanks so much for the feedback!
The game absolutely has that push and pull, but the bullet speed was something we went up and down on - I lean a bit slower too to lean a bit away from the self murderizing bullets being often more scary than enemies as you last longer.
The game does end up as more of a bullet hell than a shooter.
First working proto-type, the bullets were slower, and it was mouse aimed, but mouse aiming meant that bullet aiming would be slightly off if people wanted horizontal or vertical bullets and they'd sweep across the screen - it just added onto the player's cognitive load when the game is already quite high-stress. (We also tested locked rotations for mouse aiming (0 degrees, 27.5, 45, etc), but fell on what we currently have. That said, it might be something funny to enable for players since it usually makes the game harder)
I do agree that it would be cool to have more varied bullet paths and I've got some ideas I've been stewing on that would require rebalancing the game that I want to play around with.