If not Abeloth, I'm still holding out hope that the reason Thrawn really wants out of that galaxy is because of the Yuuzhan Vong. My memory is a little spotty because it's been years since I read the books but, doesn't Abeloth have something to do with the Yuuzhan Vong? Maybe Ezra is filling the part of Jacen Solo from the books and has been tutored by Vergere?
I know probably none of this will happen but I can dream. I really wish they had used the Expanded Universe as a storyline in these shows because there was so much material there. Now, because of the sequel trilogy, there are no twins, no Sword of the Jedi, no Mara Jade, no Ben Skywalker (Luke and Mara's kid). The stories they are using seem to have a short arc. They can't go very far without rubbing up against what they have stated as canon.