If I had to be perfectly honest, I would love a true, honest Support job. Not a healer, but a Support. Bard is way too focused on Ranged DPS and not focused enough on being a Support.

Something like Log Horizon's Enchanter class, but with better soloability.

Out of every jobs I can think of that could fulfill this role would be as follows:

-Bard (Reinvented as a Support, giving all the Ranged DPS attacks to Ranger)

-Mystic Knight (A swordsman that can enchant weapons with aether and even convert an enemy's offensive magic damage into MP regen)

-Dancer (A dagger-using job that uses the power of dance to spread around buffs and debuffs alike)

-Chemist (While it would very likely become a healer job, a Chemist is well known for its ability to mix potions together. In this way, it could be a great support job as well.)

-Oracle (A powerful spellcaster who foretells the fates of friends and foes alike. They use powerful spells that have a delayed activation, similar to "Doom".)

-Time Mage (A mage well versed in the manipulation of time and space. They can use powerful magic such as "Comet" and "Meteor", but they can also speed up allies and slow down (or even stop) enemies!)

-Mediator (A silver-tongued master of manipulation, the Mediator can temporarily convert enemies to the Mediator's cause and both encourage allies and discourage enemies alike.)

I'd be willing to play any of these.