I actually think it would make more sense to have just one Armor skill with perk branches for light, medium and heavy. It really hacked me off how you could be a master in heavy armor yet know about as much about light armor as I did a nuclear reactor. :brokencomputer:
Wear plate and then leather armor, compare, then repeat what you said
But actually I preferred to have unarmored, light and heavy armor skills (medium is slightly useless- I simply MUST agree with this)