I'm still somewhat against making spheres tiered in the sense of being inaccessible directly from Galbar. Galbar should be the hotspot for interaction between gods. Interposing spheres between other spheres and Galbar is more of a division than a unification. I'm fine with the spheres being [i]conceptually[/i] tiered so you can still have high and low planes, and I'm fine with mortals and demigods needing to traverse a number of spheres to get somewhere off-planet, but otherwise it'll essentially just make for a long commute for the gods. At any rate, I'll wait until the full explanation like BBeast.

As for a flat planet, it's neat idea, but I don't really think it'll bring advantages unless someone wants to build a story around it. I personally prefer a spheroid Galbar.