It would be Madame, the daughter of Louis XVI, who will held the reality of the power, as Angoulême or Louis XIX is not the luminary of his dynasty. She was far from progressive, but not an idiot and maybe she could manage to tune down her instincts and play ball with the parliament.
Exactly,she had her eyes open enough to consider some of Charles X's acts as a bridge too far. And Louis XIX did have a sort of Anglophile streak that had sprung up in exile. Could make for fun times, of course. But Louis XIX tends to strike me as being a good soldier, though I wonder if he would've made a good king? It, after all, only took Madame Royal a half hour to convince him to sign the abdication document in favor of his nephew - making his 29minute reign the shortest in history IIRC. Maybe he would've been like Nikolai II ("a cushion, he bore the impression of whomever had sat on him last")