Hello!
While I understand that Yoshi isn't quite found of the dual design the Arcanist class has with Scholars and Summoners, I personally believe it was actually a step in the right direction to allow a class be "built" some other way. I say that because of WoW.
In WoW, sometimes a class that is designed to fill a role (such as a Priest as a healer) can, with the proper tree, be built to fill another (a Priest could DPS as a DPS). While I love how Healers here are more "active" and actually have useful damaging skills, its different from literally being a DPS.
So, why couldn't the game receive more jobs based on the concept of a Class could spawn different Jobs to fill different functions.
My favorite suggestions:
THM -> Devout (Healer) - a Staff wielding hooded high-ranking Nald'thal Priest. Through the path of Thaumaturgy, the Adventurer would enroll in the priestly body of the Traders. The job is about using different aspects of their magic depending on whether they are in Astral Sparkle (party buffing/healing) or Umbral Shades (enemy debuffing/DPS). It would also be similar to the 1.0 THM, both in philosophy and gameplay.
CNJ -> Elementalist (DPS) - a Cane wielding Hearer who would commune with the Elementals more intimately. Their focus would spin around mastering the power of the other 3 elements they lack and using it for destruction to protect the Shroud. Like my Devout Suggestion, they would be more similar to the 1.0 CNJ.
PGL -> Dancer (Healer) - a complementation of the Pugilist's stances with multiple different Dances. While Bard's song buffs their party while they damage their enemies, a Dancer debuffs enemies while they heal the party. They would have stronger than usual AOE healings but no single target heal whatsoever. Instead, they would reduce incoming damage with their dances to protect their allies - mainly their tanks.
What do you guys think of my suggestions?