George Lucas' original plans for the Star Wars sequel trilogy would've seen Darth Maul as the overall villain. Introduced in 1999's Star Wars: Episode I - The Phantom Menace, Maul was presumed dead following his intense duel with a young Obi-Wan Kenobi. It was later revealed he had, in fact, survived his encounter, with his journey for revenge chronicled in Star Wars: The Clone Wars. After years of attempting to re-establish himself as a formidable adversary in the Star Wars universe, Maul ultimately met his end in Star Wars Rebels, at the hands of Obi-Wan in Tatooine, where the Jedi was in exile secretly looking after Luke Skywalker.
With the Skywalker saga, audiences can look back at the last three films from the famed franchise and imagine how things would've panned out if certain narrative elements were different. The sequel trilogy is controversial, to say the least, with fans often arguing about the merits of each of those particular Stars Wars movies, as well as the trilogy as a whole. Now, a new book offers the public an idea of what Lucas initially wanted for these films, which includes a different but still familiar villain in Darth Maul.
According to Lucas in Star Wars Archives Episode 1-3 The Prequels (via u/bothanspy89), Maul's trajectory would have been changed significantly had Lucas retained creative control over Star Wars. Instead of struggling to build an alliance that would help him to achieve revenge against those who wronged him, he was supposed to rise through the ranks and become a powerful figure in the galaxy. Said Lucas, "Maul eventually becomes the godfather of crime in the universe because as the Empire fails, he takes over," or at least that's what would have happened in the creator's version of the sequel movies. This effectively makes Darth Maul the narrative's main villain as Leia, who leads the New Republic, works to take him, as well as his cohorts, down.
George Lucas wanted Maul has the big bad guy of the Sequels, this is from the new book Star Wars Archives Episode 1-3 The Prequels with new interviews from Lucas from StarWarsLeaks
In hindsight, Maul had a similar arc during his appearance in The Clone Wars, albeit on a much smaller scale. Despite that, however, the story was well done and fits better into his overall narrative, which ended in Rebels. As for the Star Wars sequel trilogy, nothing from Lucas' original plan made it into Disney and Lucasfilm's movies, other than the idea of bringing in a familiar face to be the primary bad guy. That said, considering Lucas wanted the story to take place not long after the events of the original trilogy, it somehow makes sense Leia and Luke go up against someone who's long been in the universe, simply waiting for his time to execute his nefarious plans, instead of an entirely new character.
Other than having Maul as the Star Wars sequel trilogy's main bad, it sounds like Lucas' story is more grounded than its predecessors, with the New Republic essentially working to take on an underworld boss. Whether this would've received a better reception than the current canon is uncertain. Even if some like the premise of the trilogy, there are still other factors to be considered, such as the execution of the story.
Source: Star Wars Archives Episode 1-3 The Prequels (via u/bothanspy89)