Okay, I know next to nothing about Exalted
Indeed.
In this case, the information I'm presenting is specifically a rebuttal to the idea that the Exalted cannot develop new magic in response to out-of-context problems, and to the idea that if they're caught flat-footed they're entirely fucked. You can't just spontaneously acquire new powers with no basis or cost on the fly.
To put in Mage terms... I don't know, let's say you're suddenly facing a cave-in, and you've only got enough dots of Correspondence or Space or whatever to get
yourself out – but your best friend is also there, and he's going to die. You've got enough xp stocked up (or thereabouts) to buy that extra dot of Teleport Arcana, and you've been working toward developing it, but you haven't had enough downtime to actually add it to your sheet. As a result, the Storyteller says "yeah, sure, this dire situation is the incentive you need, and working on pure instinct and desperation you teleport both of you out of the cave. Spend the xp, fill in that extra Sphere dot."
In Exalted, the Storyteller is explicitly encouraged to behave that way, because that's the exact genre being played to by the PCs. Also, every power you could possibly get is already something you've been "working toward developing", because Exalted Charms are trees of powers based on Abilities or Attributes rather than existing in a vacuum.
If we imagine you've got a custom anti-teleport Charm written up that lets you just plant your feet and say "no, fucker,
you come
here, and you've got both the Athletics dots and the prerequisite powers, you're already the kind of character who deals with teleportation like that, so there's not much problem with the ST just letting you spend the xp and take the power in the heat of the moment, rather than getting chumped over and over until you can meditate the Charm onto your sheet.
The White Court isn't the lesser evil Lara Raith is the lesser evil. So long as she controls Lord Raith, the White Court is mostly on leash. And they she is probably more dangerous, personally, than any potential usurper, having her in charge is generally better than dealing with the chaos of a White Court civil war and followed by the winner deciding to eliminate those pesky wizards.
I think we can be totally honest and say that Harry's logic behind generally tolerating the existence of the White Court stems at least in part from from "they are the sexy vampires". The Black Court and Red Court, by contrast, are not well-populated with gorgeous porn stars.
The White Court aren't any better than either of them, they just a) stay out of sight, out of mind, and b) look very nice when they do show up.
...man, this is a really nice Exalted and Dresden Files General you've all got here. I might stay.