Currently, taking both of these AAs reduces the pet's overall dps as they reduce the number of Minion's Soulstealing hits significantly. I believe this is unintended as Conjurors have similar AAs without the same issue. This particular issue has been tested in VoV, RoR and the current expansion. The number of Minion's Soulstealing hits reduces by about a third and the overall damage of the pet is reduced about 20% or more if you have both Minion's Mark and Wrath of the Undead Servants.
I propose that Minion's Soulstealing receive an increased casting prioritization when you take all three AAs or simply increase the damage of Wrath of the Undead Servants to offset the loss of taking all three abilities.
I propose that Minion's Soulstealing receive an increased casting prioritization when you take all three AAs or simply increase the damage of Wrath of the Undead Servants to offset the loss of taking all three abilities.