If you can manouvere effectively in heavy armour using light armour would be a breeze.
I don't think that would be the case. Since I am a fan of the Heavy Armor, I was a lot disappointed in Oblivion with the 82 max armor value (i think it was 82). So even with Light Armor and some enchantments you could hit the cap. I long for the days in Morrowind when the difference between top end Heavy Armor and top end Light Armor was around 200 points. That is the only thing i despised about Oblivion. In the end you finish the game with the same amount of armor value for both Heavy/Light armor. So if that would be the case in Skyrim as well, in my opinion i think that the perks should provide quite different bonuses from eachother.
In example:
Heavy Armor: Provides resistance/immunity to disables, like Knockdown or Stagger ( a person experienced enough in HA should be able to use the armor as a support, much like an exoskeleton)
Light Armor: Provides Mobility (more movement speed, better chance to evade attacks).
But what i desire to be implemented in Skyrim is this. No matter the quality of the armor or the enchantments, Light Armor (even fully enchanted) should NEVER have the same value as Heavy Armor (even unenchanted), cause it just doesn't make any sense. Talking about HA and LA of the same tier. Any thoughts on this idea ?