NINJA and ROGUE confirmed

[Gilraen]

The thing is... tossed aside at Lv30?

And then there's this. Not one class is tossed aside at level 30. Using your Bard example, without the archer's foundation the Bard would just be three songs, a song buff and an AoE attack. Classes aren't tossed aside, they are buffed by the equipping of the Job stones because that's all the Jobs are, special equipment that grant enhanced stats and expanded abilities at the cost of the class' multi-classing. Ninja will be no different, it's nothing without rogue providing a foundation.