Let me put this first, audio goes long way on how the game feels. Without it, the attention span drops to under 5 minutes.
Other than that, the game is great, good graphics, nice visuals and art. The gameplay felt nice.
Also the visuals were very dark, you should have definitely increased the vision.
The problem with the game is not gameplay or mechanics, its balancing. The reload takes way too long. The player dies in 2 hits, health regeneration is slow. Once these issues are fixed, its a great game.