There's simply no way Napoleon could have found peace on his throne. The moment the Allies refused his peace offers upon his return from exile in 1815, he was doomed. Sooner or later (but likely sooner) he would be off the French throne once again. Napoleon had never faced as many enemies at once as he did in 1815. Even if he had have won Waterloo (which was entirely possible) that's no guarantee the British and Prussian armies would have been destroyed. Even after Austerlitz - Napoleon's greatest victory - the Russian army was still very much intact and Napoleon spent months and another whole campaign trying to chase them down and finish them off. So even a victory at Waterloo wouldn't guarantee the destruction of the British and Prussian armies, and while pursuing these retreating armies he'd also have to prepare to fight the combined might of the Russian and Austrian armies, and the possibility of a Spanish invasion of France from the south. I think the general consensus is that it's very unlikely Napoleon would be able to pull off another Austerlitz in 1815. His health was getting steadily worse and his good judgement was slipping more and more frequently.
But okay, even then, let's say he somehow defeats all four major Coalition powers - a near-impossible thing to do. At best, they would make a peace that would last for probably no longer than a couple of years (like the Amiens peace), long enough for the Allies to rebuild their armies and prepare for another shot at Napoleon. So long as Britain was willing to subsidize their allies on the continent (which the past twenty-two years had shown was certainly the case), Napoleon would also be either at war or living under the threat of war. Despite the love and devotion his soldiers consistently held for Napoleon right till the very end, the Emperor's popularity was slipping back home in France (and especially Paris and other urban areas). The Senate was itching for any opportunity to get rid of him. Everybody wanted peace, not just a short-term truce, and over the past 15 years Napoleon had simply shaken up too much of Europe to be allowed to reign in safety and peace.
Possibly the final moment that a long-term peace in Europe for Napoleon's empire was feasible was the 9th of September, 1812; the day before he began the retreat from Moscow.