They have tons of stories for this type of show from the various comic book series. Star Wars Tales has at least one story per issue, a quick adaptation using the actual art with some minor animation could fill out a show per season alone. Heck pay the people who made some of the fanfilms/viral video's and there's another show a season. Sounds to me like the they've either got some cash to spare and are putting it towards content or the real life show is getting a second pass (this being one of the criticisms of the Prequels that things weren't given the time to evolved and flush out) so to fill the void these additional shows are coming out.