They should just go with original stories, and maybe they could make reference to Thrawn in the new movies, saying something along the lines, they thought Thrawn was a tough enemy, but he's nothing in comparison to *insert villain here*, just to make EU purists happy. All in all, I'm pretty sure they're going to overwrite a lot of the existing EU material, with these films. It is what it is. I've never been much of a fan of the Post-ROTJ EU. Some of it is downright ridiculous. I don't think the Vong would be a good way to go on-screen, either. I'm totally fine with them getting rid of the Post ROTJ EU. Just make it non-canon, and there's no problems. To the fans of those works, that material will always be there for you to view, but since most of it just isn't that good, I think it's safe to say that LFL/Disney have no problem wiping it out. It's George's fault, in the first place, for letting the authors go crazy with material in that time period.