First of all, the game is very fun and has a lot of potential.
The last time I've played this is during DD12 (I think). Things don't seem to have changed that much but I'm sure you've been working hard on it. I'm going to nitpick and complain about things you're probably already working on / aware of but I'm going to say them anyway just in case.
- Your game really needs a flashlight, it was hard to see in some areas.
- The knife doesn't do anything if you hit objects with it. Maybe add a sound-effect + a decal
- They're probably really hard to do but if you could add ragdolls they would be very fun to mess around with.
- If you can't do ragdolls, can you at least make the corpses react when you shoot at them? Maybe make them spray robot blood or something.
- I was able to cheese a bit with the NPCs by hitting their feet at an odd angle through a door frame and they didn't react or move.
- More varied sound effects when jumping would be nice.
- The FOV felt a bit cramped to me, adding it to the options menu would be nice. Is it set to 90?