I've been looking at which classes might make for the strongest archer in PVP, and DK seems like it might be it:
Igneous Weapons - Gain both Major and Minor brutality (Mountains Blessing passive).
Corrosive Armor - Ignore 100% of enemy's physical resistance.
Dragon Fire Scale - Protection from projectiles being fired at you.
Green Dragon Blood - Major Endurance for better stamina recovery (can run a different buff for food).
Bonus - Get stamina back whenever you're using Earthen Heart skills.
I think it's Corrosive Armor that sets DK apart. That 100% ignore for resistance looks so sweet when theorycrafting with the bow. Thoughts?