Maybe its just me but its a little overly complicated lol. I can't get it to work, im testing it at 0% to see if I can crit 100% of the time or just about. Im not understanding this loltry the crit *evasion* trait.
crits are calculated on the attacking side, so in order to modify it you'll need to rework the way the hits are calculated, for them to account for crit *vulnerability* on the defending side.
but by combining crit evasion, attack elements and element vulnerability you might be able to achieve the effect.