In a duel of archers the winner is not usually the one with best bow or more arrows, but the one with more armor. (unless one seriously out-ranges the other)
Vlandian, Aserai and Battanian caravan guards have same stats and gear as normal T5 units, now the other factions, specially Sturgia do have some beastly caravan guards
I will probably change that in a mod... but again i dread the long hours it will take...