Given that an epic Wizard can get both Epic Necrofocus and Mummy Dust far, far easier and sooner than a Pale Master, this would enable PMs, who already sacrifice a fair bit, to become master over corpse-summons.
Also, from Scurvy Cur;
Potentially consider making the special PM summon spells infinite use with a 4 minute cooldown, giving the PM wizard the ability to continually summon his deathless minions. It won't make him any stronger encounter to encounter, but it will mean he has a concrete advantage over more traditional wizards in the endless font of cannon fodder front.