[Rayden]

Hope he will answer.

This is also a problem for characters that put debuff on opponents defence.
For example MG. Fire Slash reduces opponent's defense by x%.
But if opponents defence is already low, the effectivenes of Fire Slash debuff will be also low.
All this is caused by the fact that investing stats in agility and defence does not help to survive. Therefore, everyone gose for High Vitality, High Damage and low Defence.

In other words, having a proper Duel System is important for game ballance. But even better, wold be to remove defence halvening entirely. Let players have their real defence everytime and just increase monster attack power.