Is it worth using some Smithing Perks on the Heavy side if you are only going to wear Light? Is the improvement in Ebony and Daedric weapons v.s. glass worth using the perk to improve them?
Only if you are a crazy 'I must have the highest damage item" type person. when actually compared I think they come to 10ish points of damage difference.
EDIT: and to be honest, I went light armor all the way to dragon armor, but really only use the armor and weapons I get for factions/quests as I have no problem surviving and killing with them. I just use my smithing to modify items as well as making armor for a companion if I so choose to take one.