I've been skulking here for a few weeks. I'm happy that we got an actual ending but there are some pretty serious problems that I hope are answered more fully in the book. I thought that the episode had some beautiful cinematic elements and Drogon was used well. Peter Dinklage was, as usual, the best actor by far.
1) Where did Drogon go? If you have read Fire and Blood, you quickly come to realize that dragons in GRRM's world don't lose their minds when their rider dies. They generally lay around and eat until another Targ comes to try to claim them as a mount. So I doubt Drogon went far and since the only Targ left is Jon.... problematic, right? I guess that Gendry, as a Baratheon, has some Targ blood in him but that is a mighty thin line.
2) Tyrion's argument for Bran is that... he has a cool story? That is why he should be king? I mean, John was raised in secret by his uncle, went to the wall, became the youngest commander of the night's watch, DIED, came back to life, fought the white walkers, almost single-handedly raised the alarm to the realm, convinced Daenarys to join him, helped defeat the Night King, then saved the planet from his crazy Aunt. And Bran? I got thrown out of a tower by the Lannisters, disappeared, everyone thought I was dead, then I became the three-eyed raven (Which nobody understands) came back into the wall thanks to that Reed girl, then... I was bait for the Night King and my sister killed him. Which one is the better story?
3) The idea that electing a king will cause less strife and bloodshed is an indicator that D&D never heard about the Holy Roman Empire or Elector Counts. If anything, it makes it worse. Now anyone can have a claim.
4) Why is Jon exiled? As someone else said, As soon as the Dothroki and the Unsullied are gone, set him free and make him king. By the time they hear about it, they will be back in Essos and not likely to return. Plus Jon probably gets Drogon and just sinks them if necessary. It is better if Jon declines the throne and exiles himself. Still, a horrible end for a character.
5) When Sansa basically tells them all thanks but no thanks, why wouldn't the Vale, The Iron Islands and Dorne do the same thing? There's no army left after the northerners leave. The Vale is definitely the best defended Kingdom. They have no ships so the Iron Islands are free and clear and nobody even knows what that Dorne guy's name was so they won't miss him. There's no reason for the kingdom to stay together. All the great nobles are basically dead or better off being their own kings/ queens.
I won't get into all of the things that basically don't matter: like Bran being the three-eyed raven, Jon being a Targaryen, etc.