It would be cool in the sense that you'd be able to create your own piece of armor, designed for and tailored to your character.
It would be bad in the sense that it wouldn't make any sense, and would sort of ruin the uniqueness of the Dragon Priest masks.
Perhaps this idea could be applied to weapons? You could create a unique sword, war axe, mace, dagger, greatsword, warhammer, battleaxe or staff, adding embellishments, enchantments and so on.