In my experience the character builds that wear light armor are also the builds that typically make a point of avoiding getting hit. I wouldn't bother with the dragonscale, I'd just make a few suits of glass armor and use the perk point elsewhere.
You *do* want the daedric perk though as that is what you'll use to make the weapon that 1-hits >90% of the mobs in the game.
I have a lvl 46 archer/assassin whose light armor skill is mid-30s because she simply doesn't get hit very often. I should probably power-level it with summons or a wild critter that does low damage.
The thing about Dragonscale is that you can reach it without dipping into the light armor branch of the Smithing tree. Glass is out of reach if you go for Daedric unless you dump points for no reason at all in the left tree.