Regardless of what enchant you take, if i fight makes or breaks because of your weapon enchant, then something else is the matter. Your weapon enchant is such a minor thing of your overall tanking stats. If you wipe on a fight, and then say "Damn, if i had just had 35 agility, we would have made it", then you need to consider the rest of your gear and see what else needs changing. Lets say you have mongoose, and that it hasn't procced when you take that fatal hit. Chances are, 1% more dodge (from +35 agi) wouldn't have saved you.