Love the game so far. It's doing so many things well and I can easily imagine it having that "easy to learn, hard to master" sort of gameplay that keep a person coming back over and over. With that said there are a couple of things I think would be good additions to the game.
It would be nice to be able to see the health of an enemy when I hover them so I can make a more informed choice before blindly testing.
I'd like to be able to put my knife away and bring two guns into a run. On that note a give up option would be good for when I know I can't extract because I ran out of ammo or whatever; having to get myself killed would be annoying.