I find myself thinking about the implications of Navani's storyline because they're really interesting.
There's this series I adore, The Baroque Cycle, by Neal Stephenson. Historical fiction with a dash of fantasy set in the mid-late 1600s/early 1700s about, amongst other things, the Enlightenment and the rise of modern economics and nation-states. Also, the romance between a former concubine to the Ottoman emperor and a syphilitic vagabond with half a dick. But this definitely reminded more of the former stuff than the latter. Navani achieving that state of total focus on scholarship even while the reality of the situation kept beating at the back of her mind was excellent, and I think there's more territory to explore there in future novels.
And the actual metaphysics of it all are fascinating. The "sound on a plate" thing has been going on since book 1, with the design of the Dawn Cities following vibration patterns. Is this something particular to Rosharan forms of Investiture? Or is it true of everything? If all forms of power take that same vibration - the light I think is actually a bit of a red herring, the color stuff seems to descend from the sound rather than the other way around - that means that she has, in theory, already figured out a way to move Stormlight from Roshar. Just have to set it to a vibration that doesn't correspond to anything, or even silence, if that's possible. Sever all Connections and the "pull" towards the Shard that the Connection originated from disappears. Now, does this allow it to still be used... that's unclear. Lacking a Connection to a source of Light on Roshar seems to make it impossible to use it. Human Radiants can't use Voidlight, but Venli can fuel her powers with it. But does that mean that a Connection-free source of Investiture wouldn't be usable by anybody, or does the Connection carry with it a kind of whitelist where it checks for permissions, meaning that no-Connection power would be usable by anybody with powers? Vasher still being alive suggests that neither is quite right, since if he couldn't take in Stormlight he really ought to be dead, but Vasher is weird for multiple reasons right now.
And what does all this mean for people who have them? There's loads of different mechanisms for having a Connection to a particular form of Investiture - Allomantic power is passed down genetically, Surgebinders form Nahel Bonds (though maybe not always, if the first Spren bonded with Humans after their arrival on Roshar...), everybody gets one Breath, and on Sel everybody can use the local magic system with the appropriate education. It differs dramatically from world to world, but if the mechanism that Connect Investiture to a Shard are the same as the mechanism that Connects a person to a power, it should be possible to give anybody access to any ability. This is backed up by Hoid going around doing just that, though he's a unique case for a number of reasons.
It's such a statement on setting design that so many pages devoted to exploring the fictional physics of a fictional system are this compelling. Really hope we get more stuff like this in future books.
