The next update will come when I finally figure out what I want to do with the final peace.
I suspect that even with the somewhat diminished Bourbon position, the most likely outcome is something similar to OTL with minor adjustments (e.g. Finale ceded to Sardinia, Guastalla ceded to Austria, that sort of thing). The reason is that although the allied position is better ITTL, the allies can't simply dismiss the idea of landing Felipe altogether so long as Spain holds Savoy; worst case scenario, Spain simply annexes Savoy and says "there, we've got our principality." So even if the war is completely deadlocked in the Netherlands and Provence,
something will have to be given to Felipe to redeem Savoy (as the Spanish don't really have any other objectives aside from some commercial issues with Britain).
The most credible alternative to putting Felipe in Parma was putting him in Savoy. The proposed Austro-French treaty to end the war envisioned exactly this, while Parma would be ceded to Carlo Emanuele until such time as he recovered Savoy (by inheriting Naples or dying without male issue). In fact a "Philippine Savoy" was the favored solution of France, Austria, and even Spain, but in the end Newcastle's instructions to Sandwich were to allow Felipe to be granted Parma, probably because the British favored the Sardinians more than the Austrians (although this solution was still
partially at Sardinia's expense, because Piancenza - part of the Duchy of Parma - had been one of the territories pledged to Sardinia in the Treaty of Worms).
Only Savoy and Parma were given serious consideration in the peace conference, but a few other options were considered during the war. There was a Bourbon proposal, designed to get Carlo Emanuele to switch sides, which envisioned Felipe becoming King of Sardinia (just the island) while Carlo Emanuele would gain the Milanese and become King of Lombardy. "Philippine Sardinia" isn't actually a terrible idea; Carlo Emanuele didn't care much about the island, and of all his territories he would probably mind Sardinia's loss the least. Felipe, meanwhile, would become a king instead of a mere duke. But since Sardinia was the source of Carlo Emanuele's royal title, it's impossible to envision this working unless a "Kingdom of Piedmont" is created from whole cloth, Prussia-style, and I'm genuinely unsure as to how that would work or whether it would even be considered. Such a "create-a-title" had been proposed before during the war - specifically, creating a "Kingdom of Moravia" for the Elector of Saxony so he would have a heritable royal title (as opposed to the Polish crown, which was elective). Presumably the emperor would have to be involved, but Maria Theresa wasn't very fond of the Sardinians and I don't know whether she would have authorized her husband to make it so. For whatever reason no such proposal was discussed at the 1748 talks IOTL.
Your thoughts, as always, are welcome. I'm a little tempted to do something different, but the more I read, the more the logic seems to point inexorably towards something approximating OTL's peace.
Maria Elonora sounds like a very interesting character. I take it that this brief possible affair is only the beginning of her part in Corsica's story?
That would be a fair assumption, yes.