Commander Luke is from Hoth. That's long, long before the entrance of Ewoks into Luke's story. They hinted that we'll need characters involved in his story between the beginning of ANH and the escape from the Death Star before the end of ANH; that would be Luke, Obi Wan, STH, Leia, and perhaps R2 or Han Solo, depending on whether they want to gate Commander Luke behind a legendary or raid character, which many people may not have. It's even possible that you might need Jawas, Tuskens, and maybe even Vader/Stormtrooper, but I find that much less likely.
