I was primarily thinking about this as having some variable reactions to the elemental surfaces.

Since they are the biggest thing in the OS games, if all enemies avoid them equally - the surfaces as well may not be there.

Its true we can use choke points in some places, but most of the areas are spacious enough for enemies to find some path around them and the path finding in Larian games is, funnily enough, too good.
And its also true we can basically bomb an enemy with some surface effect, but thats not really the solution either.

My suggestion doesnt require anything more complicated then some obviously brainless or non human enemies like animals and similar being less cautious about them.
I think ive noticed some cases of such behavior in previous game although i dont know if that was intentional or just a consequence of Ai not being good. It felt more like a random thing than an actual behavior.

The version of OS2 i tried had voidvoken at that church ruin walk into fire and that felt satisfying.

As for the other Ai behavior related things, if they can find other ways to make some enemy types behave a little bit different all the better. But i dont think thats very necessary or that it should be something very complicated. As long as animals and other creatures of that "kind" dont behave like elite commandos im good.