The Nightsisters
The Nightsisters – seen in The Clone Wars – are an ancient matriarchal order, who rule the planet of Dathomir. They’re akin to a coven of witches, insofar as they present an alternative view of The Force, by drawing upon it in a different way to either the Empire or the Jedi. The Nightsisters generally keep themselves to themselves – choosing to focus on their own social matters and not involving themselves in the politics of the Empire, or the Republic.
However, they do deal unfavourably with anyone that happens to arrive on Dathomir, and they’ve also had dealings with Count Dooku during the time of his Separatist Movement. Indeed, Darth Maul is the son of Nightsister Mother Talzin. This could be the focus of a movie plot itself (since it ultimately leads to the extinction of the Nightsisters) but equally, a story could be woven of young Nightsisters, growing up in this very specific, matriarchal culture, and learning about where it fits within the context of the galaxy and The Force.
There’s a great deal of scope here for world-building in live-action cinema, with the introduction of a set of characters new to the film franchise. The nature of the witch-like Nightsisters clan means that this story could also incorporate elements of horror genre more than any other in the Star Wars series. As such, Karyn Kusama would be a great choice to direct.