Alderaan
Do you think we'll see the planet that gets blown to pieces before it gets blown to pieces? Leia grew up there ya know, and GL wouldn't just have a planet blown up and us not know about it's inhabitants at all, no information whatsoever except EU. Then we have Bail Organa. What about him? GL will probably expand upon the character, because he's Leia's "father".
And Alderaan was part of the Clone Wars. In EU and the movies, the people of Alderaan put a ban on weapons after the Clone Wars.
"Alderaan is a peaceful planet, we have no weapons!"
--Princess Leia, Episode IV, A New Hope