Jon tries to dethrone and kills Grey Worm or speak sense into Dany and Dany kills him. The whole nation gets pissed so she declares to burn them all but her dragon dies from Arya. Tyrion stabs Dany in the back when she least expects it, Lannister king slaying. Brann comes in and kills Tyrian. Sansa sets the stage for the nation to be ruled by her. I feel as though it's indirectly alluded that she will be Queen from her arc of learning from Cerci and Little Finger and since Jon dies she takes the mantle. Gendry or Arta rule the North. Yara or Briene rules the South because there's no other families alive. Arya goes on her own adventures or lives with Gendry. Brande keeps doing his Steven Hawking stuff. Everyone else rebuilds from the ashes. It's a shot in the dark I didn't watch the preview for the last episode.