My prediction:
Playstyle: Like SMN. Generic AoEs and Generic ST depending on "summoned" beast.
Beast book: Gather beasts and add them to your book.
Weapon: Something that isn't a pokeball.
That's probably it. If it has literally any depth at all, such as teaching abilities, feeding them, letting them have children or using them as mounts, I'll be surprised, because depth isn't something SE usually bother with in FFXIV.