The Austrians wanted Napoléon II, the British wanted Louis XVIII and Alexander wanted either the duc d'Orléans or a Napoleonic marshal (IDK why I think it was Bernadotte).
I've heard the British wanted the Bourbons - not sure why
I've heard the Austrians wanted the Napoleon II (makes sense because his mama is Austrian)
I've heard the Russians wanted either due d'Orleans or a Napoleonic Marshal (elsewhere I heard they were OK with a republic) - not sure why
If it is true that Russia found the idea of a French republic preferable to the Bourbons, or even just tolerable, why was that outcome anathema to any of the other powers, like Britain?