I think the crux of the issue is linked to collisions. If it were possible to have enough precise collision boxes*, one could easily simulate all the interactions with the various components of the armor and the associated damage, including a plate with a realistic behavior. It would be useful not only for the arrows, of course (appropriate behavior with the various types of weapons, precise reference for impact sounds). For the right balance it would be necessary to make archery much more demanding, for example by reducing the exact moment useful for an optimal shot. The result would be realistic and fun at the same time: more difficult shooting but with the possibility of aiming at discoveries or poorly protected parts.
It would also be right that the damage of all the weapons was considered simultaneously in the three types, cut - perforation - impact, to be interacted with the different materials.
Example - (values are indicative, just to make the idea)
Sword: Damage: 50 [Cut: 0.8, Per: 1, Imp: 0.4]
Ax: Damage: 60 [Cut: 1, Per: 0.25, Imp: 0.75]
Mace: Damage: 50 [Cut: 0, Per: 0, Imp: 1]
Arrow: Damage: 35 [Cut: 0, Per: 1, Imp: 0.15]
Plates: Protection: 50 [Cut: 1, Per: 0.75, Imp: 0.9]
Chainmail: Protection: 35 [Cut: 1, Per: 0.4, Imp: 0.1]
Leather: Protection: 20 [Cut: 1, Per: 0.70, Imp: 0.85]
Cloth: Protection: 5 [Cut: 1, Per: 1, Imp: 1]
To these values should be added the modifiers for impact point, speed etc ... It may seem complex but in reality it would be automatic.
I believe however that the Taleworlds are enough awake to have already thought about it, so if it does not, it means that the calculation must be too expensive ... too bad, it would have been very cool.
I hope I have made the idea and not made myself ridiculous.
* (for example defined on UV map of a single mesh of human form?)