So my understanding of Bard and Machinist is they have the lowest pDPS as a trade for their support skills. If Dancer is the same I don't think they'll need to lower it even further compared to those two because they will have plenty of dps downtime due to reapplying their dance buffs throughout the battle. So they'll have the lowest dps of all jobs when played optimally because their focus is buffing another person even more then has been seen in the game's lifespan rather than their own dps.

I'm not really sure if this matters in meta discussion (I'm not a raider) and padding out one person's numbers matters more in the meta then Dancer probably will end up meta. But if Dancer is working the way I think it is then it shouldn't be game breaking and could be swapped out with either Bard or Machinist and the overall party DPS should stay the same. Accounting for the dances actually being balanced instead of over or undertuned.