Really impressive how much you've managed to do! Especially the cutscenes - you pulled them off really well, I loved the camera work.
Environments are very nicely modeled and dense with detail.
There were a few camera hiccups here and there - but nothing game-breaking.
I kind of wish there was a little bit more to the stealth mechanic - as it is, I was able to just hold space and walk past all the enemies on the level. Would be cool if you would add some clutter on the floor that would make noise and alert nearby enemies - that might make the encounters a bit more tense, I believe.
Also, those scenes with 2D illustrations - super well done, and voice acting, even if a bit amateurish, still sets the right mood. Amazing work!