As far as ive seen and played, in order to get the most out of upgrading a set of armour, you need to have the perk to create that armour. IE without a perk in Elven Armour but in Dwarven you can only get to a max of flawless with elven armour but legendary with Dwarven.
This is with 100 in smithing by the way. Also without Arcane Blacksmith perk you can not upgrade enchanted items
No it is not.. nothing in the game is exactly necessary.. its all how you want it to play out. if you hate smithing dont do it... if you love it ... do it. --- There's only one Return, and it's of the Jedi.