Really cool art and SFX (some background music or ambience would be nice). Gunplay is fun. The Damocles' reload animation was really neat. The ability to switch weapons via the scroll wheel instead of just the number keys would be handy (assuming you aren't planning on using the scroll wheel for something else).
I liked reading the terminals, although having to press E twice (once to bring it up, and again to show the text) is probably unnecessary. Just once to bring up the text is probably enough IMO. And I would've liked to be able to scroll the text vertically with the W and S keys.