I have two books to push.
The first one is - The Napoleon options: alternate decisions of the Napoleonic wars by Jonathan North
The second one is - Rites of Peace The Fall of Napoleon and the Congress of Vienna by Adam Zamoyski
The first one describes scenarios where France could have won the Revolutionary/Napoleonic Wars. Some scenarios are a French invasion of Ireland, Napoleon conquers the middle east. Some are implausible such as France winning in Russia, and that leading to Russia's collapse into anarchy.
The second one describes the the latter half of Napoleon's reign. Pretty much it details attempts of France to get a peace in 1813, the issue of Saxony almost causing another war, the emergence of Prussia, which Bourbon to restore to the French throne, and Napoleon's Hundred Days.
Both books can be found on Amazon.com.
Wishing you well, his majesty,
The Scandinavian Emperor