Moving to here before I derail the rage thread any more.
New extermination system ideas:
Have Duiran rangers call off on CT if an exterminator is hitting an area. Ranger has to be alive to issue the call (may wish to remove the log of the ranger death so things can still be done in secret)
Have a willpower draining def that detects globally for exterminations and procures a line. Have that line also tell you the room if you happen to be in the area at the time.
Slow down extermination time to that of splicing wormholes so you cannot clear a whole forest before anyone can react.
Have Shamans/Sents have an ability similar to LEYLINES that will tell you how many exterminated rooms are in an area. (must be in area, will not tell global numbers)
Those should make patrols be less tedious, give you a fair shot at detecting when they're occurring, and still allow enemies to have a chance to accomplish what their goal was.