What it comes down to is, why bring a dragoon over a bard or a blm? Bard + Blm covers sleeping and aoe damage, as well as both physical and magic attack types. All this is done at range, and can be positioned in whichever way required.

IMO, melee NEED damage buffs if they're going to be punished so hard with boss mechanics like coincounter, chimera, and mistress. All that time the melee can't run into "bad stuff", the ranged are far surpassing them in damage. I'd love to say melee are just as viable currently, but it's just so much easier to use to clear all the current content with all Bard DD, all Blm DD, or a mix of both.

oh, and the reason I don't mention warrior is because we can use one as a tank, it will do all the damage of a dragoon, AND serve a tanking role as well.