Can we just take a minute to appreciate the differences between Ozai’s coronation and Zuko’s? Because they’re literally as different as night and day.
Ozai’s coronation is held in conjunction with a funeral, and if that’s not a sign of things to come I don’t know what is. The fire sages speak for Ozai, spewing lies about his father’s dying wish.
Zuko speaks for himself and he speaks from the heart, promising to restore honor to the fire nation and balance to the world.
Ozai stands alone, surrounded by subjects all dressed in the same hooded robes, and when he is crowned everyone bows in silence. Everyone, even his own children.
Only the sages bow to Zuko. (And only for a moment.) The courtyard is filled with Zuko’s friends and allies from around the world, all of whom cheer wildly when he is crowned. He does not stand alone, but rather insists on sharing his big moment with Aang, the Avatar, the person his nation was so intent on destroying and the person he himself previously saw as a mere means to an end, now one of his best friends. He even insists that Aang’s the “real hero” of the day.
Also, it's a small thing, but it seems that Zuko didn't even bother lighting the ceremonial torches on either side of the courtyard. Fire is no longer the element of the enemy, but Zuko no longer sees it as the 'superior' element, either.