If you're having trouble using light armor, skill up Blacksmith and rush to 30 for the Elven set. It weight almost nothing and offer high defense, excellent for sneaking/stealth kills.

Horses are ridiculous strong in this game. I had a dragon attacked me and my horse proceed to attack it.
My Lydia (who was super decked out) and the horse ended up doing most of the damage.

I don't even remember what's the main quest anymore, just going around gathering ores to raise my blacksmith level.