Personnal experience:
Our comp is MNK/MCH/DNC/RDM.
We have 2 rangeds, and the worst caster. We cleared E3S week 2. Any job is viable, aka you can clear content with it, it's not a dead job.
Our DPS was far from bad, we even cleared E3S on enrage after a Healer LB3!
But our Dancer was previously a Dragoon, he was tired of the job in SB and now he intend back to Dragoon because our DPS is low for the sole reason that we have 3 jobs that are not in the DPS Pantheon. In other words: You can't play the job you enjoy because you'll put more work on the rest of the party.
We have a strong desire to tackle Ultimate but without adjusments on ranged, we would have to work and perform more than half of the other comps because we don't have the right jobs, how is it fair? It's not like the mobility would make give us an incredible advantage.
We meet E4S DPS requirement with a small margin.
But because we have 2 ranged, our group cannot afford to make more mistakes than a MNK/DRG/BLM/BLM comp.
The irony.