In a way we can also thank the soviets, by funding the german communist party to destabilize the newly born german republic they pushed the establishment to embrace reconciliation with France.
Trotsky permanent revolution and it's funding of communist terror cells throughout Europe backfired...
Napoléon rose through the ranks thanks to the opportunities the french revolution gave him, something that would not exist in any of the italians states. I don't believe he would do as well or even choose the same career path in another set of circonstances. He might choose a mathematician...
Bonaparte became what he was thanks to his education in France. Would he still get a good quality education if Corsica is still controled by Genoa or even an independent republic of Corsica if France do not buy it?
The problem is that none of the french north american colonies were any similar to the British. You would need massive migration to the colonies for a french US or Canada.
French african colonies weren't settler colonies etheir.
Russia is tempering into french sphere but forget that France too can play that game. I think the Ottomans will soon gain french instructors to help rebuild it's armed forces up to french standard or close to it.