I'm also doing a Taru Taru white mage, black mage combo. I'm just debating the order. Do I want to be mostly a black mage, with some respectable healing ability, or mostly a white mage, who can also deal modest damage. My experience from prior FF's is that lower level healing spells are more valuable on their own than lower level attack spells, so I'm leaning towards my final character being Black with a White sub. I dunno, really.