Would a tougher stance by Britain regarding Corsica have led to war with France in 1768? And what would that war look like? I've read that the French were surprised that the British didn't push harder over Corsica, but whether it follows that the French were prepared to go to war is another question. My feeling is that it would lead to world war, but I'd be interested to see other opinions. And feel free to send me to an existing thread if it exists; I didn't find one.
Here's my thinking: Louis XV was sick of war and prevented war between France/Spain and Britain over the Falklands in 1770, and then he fired Choiseul because of it. However, I'm not sure Louis could have resisted war over something so close to France, especially if French troops are being killed by British-supported Corsicans and supply lines are cut by British frigates. So Choiseul probably gets his war and things get out of control from Loius.
Now you've got France and Spain fighting Britain. Prussia and Russia support Britain. Choiseul gets the Ottomans to fight Russia, and Austria moves against Prussia. The Netherlands would stay out unless there's some pro-French faction at the time. (The Netherlands also has to want to be destroyed, but that never stopped them OTL.) Sweden might even join the fray - I think they were pro-French at the time.
However it turns out, everyone sends a lot of money to the bottom of the ocean and brings Armageddon to France that much closer.