With Aurene's death, there will not be any hope left, even the Pale Tree's light or Caithe's connection, not even Joko's magic will play any role. Countdown till Kralkatorrik consumes the Mists and Tyria. We'll have to stop it, no matter the consequences. Help will arrive from Beyond, Astral creatures will want to make a bargain, Harbinger of Woe meets with us, we'll be choosing between staying and perishing on Tyria with Dragons, or we'll leave to the new Tyria, new beginning.
With a massive evacuation out of Tyria, sending the word out to all Race Leaders, united powers will concentrate Kralkatorrik's magic thanks to Astral Creatures and Echoes of the Spirits from the Mists to open a portal through the 'Light' we saw in the Shattered Observatory Fractal, during our departure from the Mists in A Star to Guide Us.
Tyria will not change significantly, beside we'll see some new bio systems, new animals, new flora. Divnity's Reach, Lion's Arch and all other maps will stay as they are, but the history of those regions will be different. Kryta will have a different ruler, there won't be the Pale Tree, there won't be Dragons, but our new enemies will be Astral creatures.
In this new Tyria we'll find out that the hero of this world is actually Aurene, that obviously won't have a clue who we are, she will be looking differently, not affected by the dragons' magic, nor she will look like Mordremoth. She will be different. And she will be able to talk. Her death on the previous Tyria made her unite with Aurene from the New Tyria, so there has been Aurene in the New Tyria, but her consciousness from the dead one is still in dormant state.
Crazy theory, super crazy... But I believe that there won't be use staying in Tyria after Kralkatorrik's death, I think Asura (Taimi)'s simulation will show that Tyria will be destroyed no matter if we do, or don't do something.
Before 'All or Nothing' we got an info that "Devs are promising that the landscape of Tyria "stands to be reshaped" as a result."
The oldest and strongest emotion of mankind is fear, and the oldest and strongest kind of fear is fear of the unknown.
H. P. Lovecraft