I will be satisfied with nothing less than a gigantic Pinwheel shaped fortress in the sky that generates super-cyclones and typhoons, that operates only when Nami, its biological component, is safely tucked naked into a water-fillled tube in its control grid. Or maybe there's dozens of Nami-lite clones it produces and she's the original or something. It makes too much sense.
Nami's weather powers, even from the very, very beginning of the series, along with her past, were abnormal. Sanji had no mention of his past, it was open-ended and hints were thrown that he was royalty and definitely had super-human strength (which at the time needed no explanation. Zoro and Luffy and plenty of others were just beasts just because, like with Big Mom later on.)
Nami, however, was always highlighted and stood out for her powers and her past was shown to be strange. She was found my Bellimere somewhere on an island that apparently was attacked by something. Pirates? Was it said? I don't recall, but she finds Nami just... lying there. No attempt by Bellimere to find her parents. No attempt to determine if they were alive later. She arrives on her home island apparently retired from the navy, but we never actually see her do it and its odd how she just goes from finding Nami to saying she took her with her, and in a small boat at that.
I may well be misremembering a lot of details. It has been years since I read it, but I recall there being some oddities that stood out very much that upon scrutiny were really "funny" or "odd". The kind of foreshadowings Oda was best at, since it basically gives you major nudges to something that but actually does so by excluding what it is alluding to, and all while conveniently leaving out details that make a different, simplified backstory. Even now, if Oda so chooses, he can leave the whole backstory with Nami as it is, and there would be no plot holes, no loose ends that matter at all. We can assume she's an orphan and a pirate raid or war killed her family. The trauma caused permanent amnesia to the sad events. And so Nami recalls nothing. It's simple and works.
But it is an assumption. We assumed Pluton was where it has been implied to be, somewhere in Arabastia. Crocodile was absolutely sure. I am almost sure, but not at all positive due to not reading any official, newer translations at all, or anytime soon, that Cobra or Vivi or somebody basically confirm that yes, the warship's buried somewhere in Arabastia and the poneglyph just showed its location there.
That turns out to have been false, and very, very well played by Oda. I actually think that he intended for it to be Arabastia, same as he had planned for that arc to be the end of One Piece if it had to be. But it was popular, and he moved on, and some threads in the story had to be reworked. But by not explicitly giving us certain info, and instead only implying or letting characters give their limited viewpoints, he steered around locking himself to specific plots or world building that could be filled in later if needed. Like with Sanji. No need to have his backstory, but when it became useful for Oda, he added it in.
Now, back to Nami. Same with Pluton's location, we are not told enough about her story for it to be concrete. And as I said, it's got funny bits.
The "funny" stuff is, it all has to do with weather. I believe she's found on her island during the rain, not positive on this at all. But she is alone and nothing's said about her island or its fate, where a single line of dialogue would suffice to explain it. Then, the ship she's on is shipwrecked in a storm and Bellimere takes her aboard a lifeboat to reach their island.
Then the weather is really, really good for oranges. Perhaps a subconscious act on the part of Uranus/Nami, to help her foster-mother's business? Which turns out to hurt it, actually...
But more substantially, Nami has amazing weather powers. Arlong praises her, even willing to let his bais go, very slightly, because he realizes she is an amazing resource. A little girl. A very frightened human child! And yet he believes she has cartographic skills like no other. Because she has amazing skill with reading all weather patterns and ocean currents.
Thematically, as well, she only first smiles at the sight of a pinwheel, a weather toy. (And one that looks cool and also happens to resemble typhoons. Come on, Oda! Don't fuck up Uranus and make it an saggy old Elephant that looked like it crawled from its grave with animals living on its back like fleas. Please. Make it a giant pinwheel, a Storm-fan of unbelievably monstrous potential quite appropriate for something named for the God of the Heavens.)
Back to her powers. Nami's weather abilities are reliably used to save the crew from sure death on the Grand Line continuously. Everyone else who survive has amazing luck, apparently, that the Straw Hats apparently don't or didn't, as they ran straight for a terrifying cyclone. This is the best piece of evidence to date, really. Vivi very specifically states that these cyclones are unpredictable. That Nami's powers are just unique, it has nothing to do with technique or keen senses she honed. Nor is it a Devil Fruit. Nami simply instinctively "knows" or hears/feals the weather patterns. Interesting her greatest feat as a navigator actually takes place as she is in a nigh-unconscious state... implying that her powers are latent and not at all under her conscious mind's control.
Then she has the climatact. A gag weapon. But it later begins to actually produce serious weather phenomenon. Yes, with dials and later... weatheria magic.
Weatheria is fascinating. Because they are a society that is existing both in the Sky and on the surface, something that seems extremely unique to them. Going to and from the sky islands/ White Sea and the Blue Sea is either fatal or extremely dangerous. You'd think the WG would have taken over them by now, those weatheria magicians. But they haven't. And they have some extremely impressive magic. Could they be the remnants of those who built/operated Uranus?
And of course, Robin has said absolutely zipp about Uranus or its true nature. Maybe it is not Nami specifically. And I doubt it. But I DO want her to be deeply connected with it. There is indeed good indication she is, given her weather sensing and obscure history. There's certainly a story there on her island that killed her family or original guardians, if she had any, that has not yet been told. Perhaps Uranus is why. Maybe Nami inadvertently killed the people on the island or something. It's not at all impossible. Or was there when Uranus did it.
Also, we suspect maybe that Dragon has Uranus. He almost assuredly has the Wind Logia or a weather manipulating power that involves winds. When the storm srtuck from the sky to save Luffy from Buggy. Nami mentions being vexed about it, because she sensed no storm approaching... the Natural weather, she is literally in absolute synch with it.
My guess is the storm was brought by Dragon with his wind powers, or maybe Uranus used its power to move the clouds, and its actions are outside Nami's ability to trace. In other words, her abilities with Uranus are exactly like what she's doing as a navigator, they are for making Uranus more efficient by reading weather data... she is the meteorological component to the Superweapon that makes it run at its best, or possibly at all...
Or maybe, according to Fox666, if Uranus is a location, then maybe Nami is the one who is supposed to go there? Maybe Uranus is a temple like structure, and she is its priestess/oracle...