Hey guys, I have a lot of catch-up reading to do on this forum but I hope this hasn't been said yet and if it has, I apologize in advance!
But something I've been thinking about lately: Pluton’s Clue Poneglyph was found in Alabasta (founded 500 years before the Void Century). Poseidon’s Clue Poneglyph was found in Shandora, which was Jaya at the time of the Void Century. Does that mean the Uranus’ Clue Poneglyph is on an island with a kingdom/civilization that existed during the Void Century?
This would actually disqualify it from being on Raftel as we know it (assuming that Raftel is some sort of secret, deserted island with One Piece on it). I don’t exactly have a list of kingdoms that existed prior the Void Century, but Fishman Island definitely did, as did Ohara, along with a slew of other places we haven’t even heard of yet, I’m sure.
The other thing is if Pluton is Hell, Uranus is Heaven and Poseidon is the Sea, does that mean Gaia exists somewhere as the Land? I know the Neptune said there’s only three, but maybe Luffy is Gaia (being that he can only fight on land) as a carrier of the Will of D. Eh, probably not, but fun to speculate nonetheless :D