The NPC at the bottom of Witchdrop claims to believe that the righteous will be with Halone when they die. That an Ishgardian believes such isn't surprising. Several Ul'dah NPCs reference Thal's Realm. I believe this was particularly true in the 1.0 Thaumaturge questline, where you were charged with enacting the revenge wills of those who had paid for and entrusted such wills to the guild. There does seem to be an ever-increasing amount of evidence that the soul in FFXIV is Aether. And so, from the lifestream of aether we come and to the lifestream of aether we return. With this in mind, the fact that Primals gorge themselves on aether which will not be restored takes on a whole new and much darker meaning: It would mean that primals are, in essence, devouring the souls of the departed to sustain their existence in the physical world.