That's some dedication! The fourth stage is supposed to be a wall that pushes the player to get back to the hub to buy some artifacts, but I guess with the simple AI it is doable also by just evading the enemies. The speed artifacts especially make the enemies very dumb and easy to evade and will most likely be removed or made much less impactful in future builds.
Anyway, thanks for the feedback and suggestions, we're definitely gonna consider some ways to spice up the gameplay by making the shooting more dynamic