It's... almost like a FPS??
The gameplay lacks a bit of clarity for non-FPS players but I got used to it quick.
You can just do the classic DOOM strat of "Strafe while firing" - it works (maybe even it's the optimal way to go about it) but when the player is allowed to have this as the only approach against all the enemies, it can give the impression that the game is slow-paced - especially with the slow movement. Now, "slow-paced' is not necessarily bad, but the speed feeling of the game is something to consider.
I'm saying this because I get the feeling the game is intended to have a faster pace, what with all the enemies surrounding you, and all the guns blazing. But I could be wrong here.
Some graphics with better imagery could have been useful for the weapons and grenades. I still don't quite get the difference between the grenades.
With that said, it's good game - it's your first game too, right? Nice one. Blasting with magic guns(?) is fun, and I like seeing 2hus with a gun, it's never not funny to me. We need more sweary Mima in our life.