Would you believe after all that I forgot something....anyway. The AI line of sight needs to be a lot further than what it is if realism is one of your goals. On the first level right at the start you could stand clearly on the road and look at the two germans patrolling up and down forever without being noticed. Realism is I see you you see me given you are not a spec of dust on the horizon. That incorporated the player would be forced to navigate unseen(hint: that = stealth). They would actually have to wait for the guard/patrol not to be facing their direction before moving. And also their vision shouldn't x-ray through trees
. As I mentioned before there is huge potential here, please take advantage.