The gibbets flying into fan blades (and in-floor garbage disposal) is sick.
Dark cursor gets lost easily (minigun w/ warmup reticle is perfect)
Awesome monsters, guns feel good to use.
Slower item tooltip background scroll speed looks better imo (grenade/ mingun ammo tooltips > minigun/flamethrower)
Tooltip being under the mouse does indeed suck. I see why you wouldn't want to do it how you do in ToK because my wife I mean my wife I mean the wife I mean the shopkeeper would be hidden. I'm just centering the box below the mouse, and clamping it on screen in my game:
I could see headlamp and hear chainsaw through a wall (imo its a neat spooky feature)
Besides Space Siege, Alien Swarm (steam) would be a good place for inspiration if you're not familiar with it.
Looking sick, keep up the good work!