My favourite mode of play in GoT is archer, but only with the halfbow. The longbow takes too long to aim to be enjoyable as a playstyle and its ammo is too low to rely on more thoroughly in big encounters. The act II enemies are perfect for the halfbow in that they are more heavily armoured than the no-armour enemies of act I, some of them having helmets that require more precise aiming for the headshots, but still allow usage of the bow to do proper damage if you're willing to make the effort to make it viable.
In act III nearly no mongol enemy is unmasked, making headshots with the halfbow impossible as far as I can tell (please correct me if I'm wrong) and just killing it as a viable playstyle. It's very upsetting.
Well with Tadayori Armor it makes notching the longbow quick, add in a couple charms and You'll be able to use the longbow fast and effective. I have 4 armor load outs (turn on in the options menu.) So I have my Archer gear (Tadayori setup with range charms) and then when they get close I switch to Clan Sakai armor. I also have dueling and then travelling armor so I switch armor and loadouts often.
Also I believe you can still shoot them in the body with half-bow, and even set on fire with flaming arrows.