AI generals too influential?

[Ignopotens]

I've noticed the nigh-invulnerability myself

For some reason the Maks sent their faction leader alone into my territory, so I sent a unit of hoplites and a unit of Getai skirmishers to try to assassinate him. At one point in the battle, their leader was entirely isolated from his bodyguard, and completely surrounded by no less than 6 hoplites at any time, all stabbing him with their spears. I watched him recoil under blows for upwards of 2 minutes (he was being stabbed so often that he was only able to dish out 2-3 blows of his own in that entire time) before miraculously escaping through my own troops with the remaining 5 bodyguards (out of the original 62). It was really just absurd.

[Ravenic]

I've seen them be swarmed by literally hundreds of Cavalry, and fight them alone for about a minute, and then single-handedly kill about ten of my cavalry.

I mean...come on.

[Kralizec]

Always have a unit of light cavalry waiting nearby to hunt down the general once he breaks out or routs.