I finally tried out the various armor levels on enemies, and so far it seems pretty good for most kinds of damage, slashing and blunt, in that armor converts slash to blunt up to its armor level, and cancels blunt damage a bit. However stabbing and piercing damage behaves a little weirdly. All armor appears to deflect stabs and pierces up to its level, which for knights is pretty high. But having worn some of the armor, I can tell you, that's not how it all works. Plate armor definitely will deflect depending on the angle of the plate, and the force behind the weapon, so its fine if that deflected those, even though a good sharp point on a polearm at a 90 degree angle would definitely pierce the armor but anyway, leather and chainmail and gambisons definitely don't protect like that.

Chainmail with a very small ring size would definitely protect against stabs and pierces, but since its flexible, that damage would become blunt damage. And of course, tips can still technically get through, but bottom line is that like slashing, all damage should be blunt damage.

Leather and gambisons are similar so I'll group them together. They are pretty good against cuts, but they won't stop a stabbing blade or an arrow completely enough. They will arrest a fair bit of force, so they can reduce the damage, but they won't turn a stab into a blunt hit unless its realllllyyyy thick or the blade force is really weak.

And although the blunt force will not be as deadly as a slash or stab, it's still a fair bit of damage. I've known people who have broken bones after getting hit with a full (blunted) longsword cut, even when wearing a modern quilted gambeson. Its rare but it happens. An edged weapon hit would make it less rare.

So anyway, if it was technically possible, armor should be broken up into zones and behave accordingly. It would make it possible to kill or disable through armor with stabbing weapons if you aim correctly.

Also if you've made it this far, another minor armor thing. All armor should make it harder to dismember. Any material will greatly impede the ability to make a clean cut. (Try it at home with an old shirt!)