I think that Ninja, Monk and Dragoon can be balanced properly... There just needs a few minor tweaks. We're all so fascinated by that DPS number in a parse we forget that Dragoon is supposed to have burst, and if SE pushes them further into a burst role, this will be exactly what they need... As well as that magic defense boost. Ninja has burst, and sustain, but their burst is not that much greater than a Dragoon, nor their sustain as high as a Monk, meaning they are a middle group. Monk is pure sustain with a wee bit of boost if you choose to stack critical on crafted gear, and that is fine since they need a little bit to ramp up to their sustain state...

However, as I said, there just needs to be a few tweaks and it will all fall into place, hopefully.