Its a shame that arrows don't get a boost from Archery skill level/perks. Easier to just use Iron Arrows for everything and swap to your best type for certain boss fights. The rarity and cost of the better arrows doesn't really make up for ~10-16 extra damage they get when your bow probably does 100+ by that point. Though the bugged Marksmanship potion is nice since it increases everything (bow, arrows and all other weapons).