On legendary. On novice, I would have said no smithing no questions asked, but I dont want to spend 20 arrows on a single enemy (and risking being caught after each one, and otherwise Im dead as soon as I see a random dragon attack, lairs can be backstabbed). A 200-ish damage daedric/dragonbone bow (with fort archery gear) will do around 50-70 damage on legendary, which is perfectly reasonable for an assassin.
The pros:
Legendary smithed weapons (though these can be achieved with 23% smithing gear for lv 192 smithing without the perk)
Dragonscale armor (cant decide between this for matching the dragonbone bow or the worn shrouded armor for aesthetics, might pick daedric if i go shrouded)
The cons:
takes 5/6 perk points for something that can be bought at a high enough level