armor isnt capped, but as i noticed i had a 17k with buffs and rend 21k armor set and the dmg diff from a aim of a 1,7k dex rog was only 1k diff, so in my opinion as higher, your armor goes as less dmg it will reduce, its not like you will get unkillable if u are full armor. Also in my opinion hp makes tanky, armor reduces dmg, so maybe mix both or go for full str