Alot of FF jobs do seem to overlap though.

BLU, Morpher, Mime, Dragonkin

Summoner, BST, PUP, Dragonkin.

To name a few.

Isn't a Morpher and Mime just a BLU?

Isn't a SMN just a Magical Beastmaster?

This is an issue they had in XI with DRG and BST. BST could tame dragons (Puk), but they did not want to add dragon pets to BST, because it was "Lore breaking" for DRGs or something like that.....Notwithstanding BST in Dyanamis had Wyvern pets. XI DRG was a pet job for some reason, guess a throwback to the Highwinds iirc.