Cool idea, but the stealth doesn't work - as soon as I'm within range of an enemy and not blocked by a door or wall, even if their vision cone hasn't touched me, they know I'm there and make a beeline for me (and will continue going straight toward me even if an obstacle DOES come between us, like me moving behind a wall - they don't seem to have good pathfinding).
Half a star because, even though the basic gameplay doesn't work, I do like the idea.