Melee Combat: Heavy Armor vs. Light Armor
From the looks of things the only differences between the two skill trees are,
- Tower of Strength (Heavy) 50% less stagger vs Wind Walker (Light) 50% Stamina regen rate
- Reflect Blows (Heavy) 10% chance reflect dmg vs Deft Movement (Light) 10% chance avoid dmg
I don't know if you reflect 100% of the damage, thus negating it, but I would assume so, otherwise the light armour would be much better in that respect.
Personally I've been stacking Stamina a little to get around this as I use heavy armour, but then again I can tank much more than my follower who is in Elvan armour. Don't forget that you can move quicker and quieter in lighter armour also. I think it's more about your playstyle. Also extra Stamina points increase your carry capacity.