One thing that slightly annoys me in Thief is that the AI always assumes a body is dead, even if they're just knocked out with the blackjack. I think it would be nice if they AI could tell the difference and reacted slightly differently (obviously both would anger a guard, but slightly more so for a dead body). Perhaps whether they can tell the difference would depend on the character - a high-class gentleman or lady might check to see if they're alive or not, whereas a dumb street thug would might just see the body and go off running.