Hello people, I'm French and a bit of a Louis XIV/Versailles buff, so posting here in case you guys would have any questions about the historical accuracy of the show and real life events that happened.
Regarding Maintenon, I see a lot of people disliked her, but I think it really boils down to her being all around a hard character to get (she's either a villain or a saint depending on who you're reading, although most French historians will agree to say she was mostly human). I get what they were trying to do with her in the show, but she also kind of feels... underwritten? Weirdly enough, considering how much screentime she gets?
I would recommend a French TV series done in the 80s, called L'Allée du Roi - I think it can be found online with English subtitles. Françoise Blanc plays Maintenon (funnily enough, she also plays Anne of Austria, Louis and Philippe's mother in the Versailles TV series) and she and Didier Sandre as Louis have A LOT more chemistry and are amazing in their roles. Valentine Varela is Montespan and I think she plays her a lot closer to how the historical Montespan really was (don't get me wrong, Anna Brewster did an amazing job but I thought she was a little too... vampish at times? Although it works with the show's context).
