“I believe this now kills every “king” in the war of the five kings, plus a lot of their heirs (Shireen, Tomen, etc).”
Yes, it now becomes the war of five queens (Dorne, Highgarden, Cersei, Dany, Yara/Asha, - and maybe number 6 is Sansa) and two kings (Euron, Jon Snow).
I don’t see how the dead prince’s mistress gets to rule Dorne, but maybe as regent for her daughters.
Highgarden’s queen won’t last long, and their challenge is finding an heir in the show, though in the books, Loras had brothers.
Yara/Asha versus her uncle is a legitimate fight unless Daenerys lends an army to secure Yara/Asha’s claim.
Cersei will go, eventually, and I’m guessing her own brother will do it per her actions destroying the Sept. A la prophecy.
Sansa will either:
A. marry her cousin and/or Littlefinger and be Queen of the Eyrie as thanks for the military support
B. marry/rejoin Tyrion and become Queen of Casterly Rock, possible to secure the North to Daenerys as an alliance with her Hand
C. marry Littlefinger as Queen of whatever domain he carves out
D. Jon marries Danerys to seal the North and song of Ice and Fire, while Sansa is Queen of the North with Littlefinger or Tyrion as her King.