Cant you just shapechange into sometihng immune to magic to circumvent that dispell? it might require a prestige class or feat to assume that ability, or you could just, you know, counter the dispell magic. And there are already ways (that i cant rememeber) to get more XP for payment. Soul sacrifices, thought bottles, whatever. What about a True Permanenced Antimagic Field? Can you say "Permenantly immune to magic becasue the Dispell magic cant get to your spells?"