One detail that I found interesting during the Elpis chapter was the fact that while Creations apparently don't have souls, the offspring of Creations do. This is how the Ancients are able to introduce new species into the world; once the initial Creations breed and reproduce, their offspring are just like other plants and animals in the world.

I suspect that most of the races we know are Creations of the Ancients (or possibly of Zodiark), and as the Sundered Ancients died and their souls recycled, those souls were born into the bodies of the races we know.

It does make me wonder why those original Sundered Ancients didn't continue to reproduce? Perhaps they did - Ancients look mostly like Hyur, except for their weird eyes, so perhaps a Sundered Ancient IS a Hyur. (Varis was right???) Alternatively, perhaps Sundered Ancients are no longer fertile; maybe they need their massive Aether reserves in order to reproduce. So, after a childless generation, they died off and only their Creations remained...