The show we should have gotten.
Palpatine's rise to power. Imagine a game of thrones style show (without the pornographic bits) about all the intrigue and manipulation leading to the grand plan that set it all in motion. You could dedicate an arch to his master Plaugeis controlling the banking clan and influencing the trade federation. His dealings with the night sisters and training Maul. Even how he met Dooku and used him to influence Syfa Dias. And for sequel fans, who his mistress was.