One of the things that we recently reported on with Rogue One: A Star Wars Story was that the film was looked at by Disney, and reshoots are happening, possibly to include a young Han Solo. Now there are reports that Darth Vader will appear, as well as a character who originally appeared on The Clone Wars show. It makes one wonder who is next, like characters from Star Wars Rebels.
Now, there are reports that Darth Vader will be appearing in the film, according to Mashable. It makes a lot of sense, as it is reported that the film will end "ten minutes before" the events of Star Wars Episode IV: A New Hope, the original 1977 film.
Speaking of characters creating a buzz, there is news that Forest Whitaker's character, which is not identified on the imdb page, could be Saw Gerrera, a character who has appeared on the CG animated series The Clone Wars. On that show, he was a rebel leader trained by the Jedi with his sister Steela.
Unfortunately, Saw loses his sister, but Lucas actually had plans for this character for a now aborted Live TV series known as Star Wars Underworld. This was before Disney bought the rights to the franchise, and it is possible that they could be using this character, just like they could adopt other characters and concepts from the Expanded Universe book series.
Most of the other characters have been identified by now, such as Felicity Jones playing Jyn Erso, the "Joan of Arc" of the story. There has been confirmation that Mads Mikkelsen will be playing a character named Galen Erso, which is a name also not listed on imdb. A complete list of characters can be found on a recent article from iO9.
Okay, so if there is a character from The Clone Wars coming to a live-action Star Wars movie, then I'm going to throw this suggestion out there: get characters from Star Wars Rebels in Rogue One. Consdiering that Star Wars Rebels takes place in between Episodes III and IV, it just makes sense to bring them in here, as Clone Wars and Rebels is still considered Star Wars canon after the Disney buyout. Heck, Darth Vader, who is voiced by the one-and-only James Earl Jones, has appeared on Rebels a few times.
The only trouble with bringing in the Star Wars Rebels is casting them. Freddie Prinze Jr., who voices the role of Kanan the Jedi, looks like his main character. Taylor Gray could pass as an Ezra, and Tiya Sircar could play Sabine Wren with a little bit of makeup and hair. The same goes for Vanessa Marshall, or Hera, and she would need a lot of makeup. Then there is Steve Blum as Zeb, who is a character that could be completely CG. In fact, I wonder if these actors were casted and the characters crafted to look like their CG counterparts. All you need to do is build Chopper the droid.
So, yes, just put the Star Wars Rebels in Rogue One. There is no way you could keep this a secret, and why would you have a connected universe on the small screen and the big screen and not pull something like this? Seriously.