Not sure if I'll ever get to it but my basic idea would probably be a RPG style game with some RTS elements -resource gathering and building mainly.

Enemy AI: (can be mechanical, animal, alien or human enemies)

-Ambush Hunter or Territorial AI: Animals of various types, humans, machines or maybe even traps or defense mechanisms that attack/are activated based on proximity -for example some critter lives in a sand pit but only attacks if you walk within a certain distance of his burrow. Can also include 'attached' animals -like a carnivorous tree- that can't chase you, automated defenses on abandoned alien cities that attacks only if you pass a perimeter or try to break something is another example (automated sentry)

-Roaming Predator (Pack or Solitary)- roaming animals, humans or machines with some brains that actively seek prey. What I mean by brains is a small carnivore or a single enemy with a handgun might not attack a party of 5 heavily armed men - the single predator might kill, injure, drag away or maim only one man and not kill a squad of 10 men. In some cases the primary purpose of these enemies might also be to capture (as prisoners) -instead of kill- or raid your resources. The capture one might be interesting as well as say they capture some of your allies and march them back to base you can try to free them.

-Neutral - some sort of AI for herbivores, mechanized collection bots, aliens or humans who only attack if you mess with them. Might be able to roll this with the territorial AI so they have values for proximity, tolerance_level (do they attack you as soon as you get near or if you continue to annoy them for more than x minutes), memory (how long do they remain aggravated at you after a confrontation; will they remember you attacked them once before and flee or fight you next time or resume normal grazing or whatever)

For the allies it would be good to be able to assign resources they collect so for example any soldiers with you might collect weapons and possibly food automatically -foraging in your immediate area- a medic with you might automatically collect medicine which would then all be available to the group. Maybe a 'forage_when_idle' option?

Anyway not sure if these are outside of the scope of what you intended and truthfully I am unsure if I'll ever get to make the game.