I'm okay with some armors becoming obsolete if you have enough money to upgrade. I don't think a high level warrior should be wearing Hide unless it's magic or that's all that is available at the time.
I'm beginning to warm up to the idea of having Strength Score to more armors and Adding a penalty to Atheletics and Acrobatics
Light Armor allows for full Dex Modifier to AC.
Top tier Light Armor: Studded Leather, Gambeson
Medium Armor allows for Dex modifier to AC but is capped at +2
Top tier Medium Armor: Half Plate, Breastplate, Banded, Brigandine
Heavy Armor has flat AC
Top Tier Heavy Armor: Plate, Heavy Plate
If anything Medium should be most protected. Since it is the middle ground, it has the most variables.
That last bit is the problem When you drop medium armor you can do things like:
- all armor: AC, Spell/Touch AC, dex caps on light armor, bring back useful mounts by imposing a speed penalty for some armors, ACP, Capped DR sometimes tied to strength or others a caster attribute, possibly more like +attunement slots for a subset of magic items akin to starfinder's upgrade slots.
- all Light armor: Low AC, usually high dex caps, low or no movement penalties, generally low ACP
- Light armor: A selection from some of these.. Baked in minor enchantments. Everything to darkvision to featherfall & swim speed possibly even including panic buttons for some like a randomized short range misty step, good to OK spell AC bonus inverse to the possible ac+dex cap it allows, +/-slot level when casting some spells(ie element*/school/etc), low if any DR, a baked in assortment of energy substitution-like cast element X get element Y result
- All Heavy Armor: Great (physical/traditional) AC. Poor to ok spell/touch AC
- Heavy Armor: A selection from some of these, moderate to significant speed/acp penalties, Frequent low to good DR sometimes based on str sometimes on a caster stat, Combat auras with interesting effects(buffs & debuffs) on those nearby, those attunement slots, combat effects that buff the wearer in various ways, etc.
* Fire damage needs to be wrenched in line closer to the other elements on the spell list