Not a bad ending to what, for the most part, was an amazing television series.
Since S2, I kept going back and forth about reading the books; On one hand I wanted to enjoy the story and not be spoiled but on the other, I knew there was a lot in the novels that wasn't being covered in the show and I was probably missing out on a lot of introspective of the various characters. Now that GoT is over, I guess it's about time I pick up those books.
I will say that I don't think Dany's arc was handled very well, at least in S8. She went from a young woman with immense power trying to do right in an evil world, throughout S3-S7 and part of S8, to Adolph Hitler over the span of half an episode. Her buildup over the course of 7 plus seasons was fantastic... then Hitler. Her turn to bad was almost as out of left field as Anakin Skywalker's in Revenge of the Sith. A good villain, IMHO, is one the audience can sympathize with. If we (the audience) had witnessed this slow moral decay of her character, her actions in S8E5 and her subsequent death at the hands of Jon would have had more impact and felt more tragic.
Drogon's actions were a bit confusing to me as well. I get that dragons are intelligent, but I don't know why he would recognize the iron throne as the symbol for all of the politicking and bad in the world or even care for that matter. HE'S A DRAGON FOR CRYING OUT LOUD! It may have worked it bit better if Drogon tried to torch Jon and melted the iron throne in the process. Now there would be two potential outcomes for this. Either Jon is incinerated and that's the end of his story, or the dragonfire doesn't hurt him as he is a Targaryen, in which Drogon thinks, okay this guy's legit, and snatches Dany's body and flies off to who knows where.
The best parts of the episode was of course Peter Dinklage. His scene with Jaime and Cersei, his prison scene with Jon and the small council scene were wonderfully acted. I'm not sure GoT would be the giant that it became without Dinklage's involvement.