Changing the name of the class is purely for identification, and for the fans. I think the current jobs in XIV are unique enough to hold their own names, alternatively if they were changed, I wouldn't mind.

I completely agree with some of the comments though, some abilities need to remain class specific to preserve the uniqueness of each job. Furthermore, I feel what'll eventually happen is the community will define a perfect set ability for each class, and if you don't possess these abilities then you're likely considered sub par.

"We need you to heal on THM, do you have Cure III ?"

The beauty of the current system is it removes the need for support jobs, you're given the freedom to completely pick and choose your abilities. Balance them to perfection so as the MAIN class for each ability has an advantage, while other classes who choose to equip the ability will still find it effective but not be at any greater advantage. That, and lock many abilities to each exclusive class. That's the most simple way to make each role feel more defined and exclusive.