Why don't you try leveling blue mage. With good evasion gears and evasion atma you can easily tank some of the seals NM with very little problem. And you have ninja and blue magic proc which are 2 out of 5. You can always bring a friend as BLM/WHM to round up your little duo group. Blue is also perfect for someone who don't always have more than an hour or two, you can gather your spells little by little at your own pace. Thief, Dancer and Beastmaster is still best if you like melee jobs. With Beastmaster you can easily solo some of the plus 2 NMs, with the right atma combos, dawn mulsum and stacks of pet food. Like others have jealously posted in other threads, a naked beastmaster can solo some of these BCNMs with just a jug and stack of pet foods +mulsum :P