FIX. THE. CONTROLS.
I'm sure mouse-only controls seemed like a good idea on paper. But in practice, they just don't work. Moving the cursor to both move and aim at the same time is EXTREMELY swkward, because I can't strafe. When enemies are pursuing me as tenaciously as that, and I can only fire at what's in front of me, I have two options: either stop and let enemies hit me as I take aim at other enemies, or keep stopping quickly, turning around, firing, and moviing, hoping that I score a hit. Either option is aggrivating. It's a pity- too. This had the potential to be an addictive shooter in the vein of Geometry Wars, but the controls ruined it.