I think Jon Snow's mortal body is definitely dead. Which is unfortunate. I think he will be transferred to Mormont's Raven and GRRM, in the next installment, will reveal that both Mormont and Snow have a conversation with each other in the Raven. And from the prologue, we learn, there's only room for one Warg inside of an animal-- but Mormont will fade, he only lingers for Snow and the Watch... some part of me thinks that Jon Snow will become the primary antagonist of the series in his rebirth... because if there's one thing this series is lacking atm.. is a primary antagonist. And before, the series had only one primary protagonist.. Jon Snow.
As for Brown Ben Plumm, I think there is much more to him.. I keep thinking of Tyrion's uncle that wandered off when Tyrion was young. Perhaps he has a role to play with Brown Ben Plumm.. Either way, I see Tyrion's lost favorite uncle playing a role soon. Also, brown ben plumm talks about he has dragon blood in him.. and tyrion says that lannisters have dragon blood in them too.. Possibly misdirection, who knows? Is Brown Ben Plumm tyrion's uncle..? Who now owns a large STOCK in casterly rock...
Arya will probably be tasked to kill Daenarys, but not right at the outset.
Sansa and Littlefinger play the game of thrones, and win. But in the end, it's only a game they've won. A mere distraction.
The High Sparrow will get a POV and will dominate the next book. Thousands will rage.
Varys will not be heard from, but will be the epilogue of the next book. Bricks will be shat.