Yeah from what I understand armor type doesnt mean a whole lot(in the end). Assuming you have the required perks and enchantments or spells.
Personally, I am still debating the light/heavy armor. Going for a spellsword, so my hp isnt the greatest nor my stamina. *shrugs* Also the whole needing a full set of heavy or light armor to make use of those skill tree perks is highly annoying. I find a nice mask and its light armor, and I am heavy, I am totally screwed out of those perk choices. Partial to the gloves for heavy armor types, pretty much everything from iron and up look nice, compared to light armor(imo). However, light armor has some sweet looking helmets and chest pieces..
So in the end I think I will avoid perking either of the armor trees and just go alteration buffs. It pretty much gives me equivalent armor, and I gain the use of paralyze spells and etc. Sorry if I was rambling abit, debating perk choices as I write this