Can you give me more indepth info about illumination?
If you say bots mainly need this to not see players into the dark places can't this be easily fixed for normal players as you just check the traceline and the player id hit to check there illumination level instead?
I also see a potential flaw with this design unless you cater for nightvision? Also you mention about following a player, that would be a bug within the sound system as well since the bot should roughly know where the player sound has stopped?
I dunno about your gaming style but the big centerid (Enemy) gives away where players are anyhow