I don't like Samurai as a Tank.
Come on, another Bi-Hander Tank after Warrior and Darkknight, that uses Swords like the Darkknight (Even though they are Katanas).

If Samurai would be a thing, than please make him a DD, so we have at least one Bi-Handed DD.

As Tank I would like to see a Vikings charakter with two one hand axes. A direction that would be unique in the XIV Universe and would fit great, due to no, one Handed Axe in the game currently.

For Ranged I could see a Red- or Blue Mage.

For the story introduction, we could be part of a War between a state of Asien Warriors (Job class Samurai) that fights a state of Vikings (Job Class Berserker).