What I would suggest is a switch in the proc conditions for both of these item sets. DD only procs when you take melee damage but Mephala procs on anything. It should be the opposite. As DD is an aura that will move with you, if you are hit at range the skill wouldn't be wasted as you could still close the distance to your target while the set holds some usefulness. Mephala on the other hand, creates a small ground aoe. If you are hit at range from Mephala, the usefulness of the set is wasted unless the ranged attacker decides to come stand next to your current position and fight (highly unlikely). If DD was on any damage and Mephala was on melee damage, this would add tremendous value to both of these sets. As it stands, they're kinda useless.