I think Season 4 will close the lore in Elona for good, and we'll move to Tyria's matters in Season 5. I think we'll see the war between the races, and the Commander will try to unite them once more, it won't be easy because the PC screwed up in Ep 5, so noone will be willing to listen to us anymore, we'll be abandoned.
Guild Wars 4 will begin - Factions anti- and pro- killing the Elder Dragons.
The races will divide and the Pale Tree will stay indifferent, because Sylvari will be reshaped in a new crystalline form, reshaped by Aurene that will unite with the Pale Tree, and we'll be able to get to Kralkatorrik's mind (as Snaff tried to) and we'll kill him from the inside. Also we'll get to know the whole history of this Elder Dragon, seeing the pictures of his past inside of his brain that is divided by hatred and the vision of hope and his fight to throw away this vision that haunts him.
Kralkatorrik is a very interesting dragon, because it seems that only he could feel how powerful hope is, he among his hatred felt hope... It puts an Elder Dragon in a different light, they actually can feel positive emotions, and not knowing them, he fights them.
Haven't you wondered why he even had a daughter? A family? Other Dragons create minions that are far from being their family members, but Kralkatorrik actually created his minion to have a family, still under his control, but as family. Also Kralkatorrik trusted Glint to reveal his secret, and that she saw the hope for the world when he said that to her, BUT why would Kralkatorrik reveal his secret to the purified Glaust? He must have told Glint about this vision before she was cleansed. So Glaust (Glint) had actually free will so she could actually think that it's hope, not doom for Tyria. His creations have some part of their own will, but still under his command, and the Forgotten actually noticed that Glaust have the potential to say by his will: "I want to be purified" and so Glint replaced Glaust.
It's very interesting that Kralkatorrik didn't have any control over his grandchildren, he gave them free will, but still his part of brain full of hatred wanted to bad to rid of them, so he just wanted to smash them away, but this vision of hope will haunt him forever, unless he accepts it.
The Forgotten dared to try to convert Kralkatorrik, so they saw the possibility that Kralkatorrik may accept this hope, but he didn't, he had too much hatred, and not a full sense of hope.
And the Pale Tree as the last beacon of hope and creation of Mordremoth, the Elder Dragon can actually show Kralkatorrik that hope can help him to understand he is just lost, and he actually has the power to defy his dark path, and be cleansed in hope, in the Dream.
So that's actually my looong speculation about the future.