11Knights of the Old Republic
Few gamers and/or Star Wars fans are unfamiliar with the Knights of the Old Republic video games, developed by Bioware. A sequel, The Old Republic, is an MMORPG that is still ongoing. These games tell a story set nearly 4,000 years before the Star Wars films. During this time Sith and Jedi flourish,
and their war is massive in scale. Technology isn't much worse than in the films, but the entire era has a heightened fantasy/medieval feel to them. Star Wars is known to be a fantasy story told through science fiction, and these stories focused more on the fantasy than the science fiction.
These video games, and all of the books/comics that surrounded them, are not canon, but they remain some of the most popular Expanded Universe stories for many Star Wars fans. A TV series set during this timeline would likely find a massive audience. Plus, being so removed from the timeline of the films, creators would have additional freedom to develop the story in any direction they choose. The Jedi vs. Sith conflict could be perfect for a medieval-style show set in the Star Wars universe. This is one of those shows that could work either as animation or live-action, depending on the scale that Lucasfilm would want to go with.