I think Stoneskin fits better as a magical ability for Paladins in this game than Cure. I'd actually like it if PLD were able to cross class mitigation tools (E4E, Virus, etc.) but they're currently limited to CNJ and MRD, only one of which has spells and that one doesn't have native mitigation spells outside of SS. I think PLD would get more out of Arcanist but obviously that wouldn't fit thematically. Maybe PLD will get more native spells in the expansion that allow them to aid their party (like how Stoneskin does now).