Hang on, someone sort me out on this: as I understand it, there were caches of the glowy green splodey stuff that blew up the Fantasy Vatican all around the city, because the crazy old king had stashed them there or something.
You know, you want a subversion, how about having Dany level the city she's trying to take because she set it on fire when there's massive quantities of high explosives underneath it? It would actually be funny as hell if you played it right.
Does it count as a complete arc when you basically just drop dead for no reason other than the writers don't have anything more for you to do?
It would have been a much more iconic ending that Dany after destroying everything she'd ever set out to own, melting the iron throne, destroying Kings Landing and the seat of royal power, was killed in a Julius Caesar sort of way with every member of the council twisting in the knife, because of the mad queen.
Though to make that work you'd have to essentially scrap part of season 8 & all of 9, rewrite it and rework it.
These two are in the show, though. In the books, the Gravedigger lives with some group of religious people, as does Clegane in the show, only I don't think we see him dig graves.
When Zombie Clegane is introduced to Cersei after her walk of shame, he is called Robert Strong by Qyburn.
A theory I like is that the Braavosi prostitute known as the Sailor's Wife is Tysha, the peasant girl that Tyrion married.
Edit:
Anyway, since I haven't watched the last few episodes and only have a few infos:
The Wildlings went back behind the wall and Jon is send back to Castle Black . . . Why aren't the Wildlings staying in the North and what exactly is Jon going to do at the Nightswatch now?
They literally have no reason to exist any longer. Arya stabbed the Night Cuck, there won't be any threat beyond the wall.
Are there any explanations for this garbage?
In reference to your edit. It's more of a lore thing that is not explored in the series due to lack of time and relevance to the greater story. IIRC before the Wildlings started descending down from the fist of the first men and started fighting the children of the forest. (Elves.) The area of the north wasn't the cold barren wasteland that it is in the books, closer to a Siberia style eco system with cold winters and hot fertile summer.
The reason for the long winters and the creation of the wall, was because the children of the forest created the white walkers to kill the humans, and were wiped out in the process. They were the ones that built the ice wall, subdued the white walker threat and then the human societies inherited it and started the nights watch as a means to keep the white walkers out.
What changed was that over the period of time and inactivity the narrative changed, and it became a way to protect the wall and the North from the Wildlings who now forced to live in near Artic conditions became a major source for conflict. Emptying out the area, known as the gift of most of it's people. (Hence the reason it's given to the Night Watch to be used as fallow land.)
Even though the Night King is dead and the threat removed as well as a return to better seasonal weather. I don't think the Night Watch in terms of political usefulness are no longer needed, as they are still administrating the area around the gift and still acting as a barrier between the civilized kingdoms and the Wildlings. (The series didn't ever seem to address beyond brief mentions, the fact that the Wildlings are something like 12 to 15 tribal groups of peoples who hate each other. The fact Mance Raider was able to unify them as a political threat, was only because of the pressures put on them by the White Walkers.)
John ends up being a weird sort of outcast character which suits his arc. (In a dances with wolves kind of way, he can't go back to being with civilized people. Just like how Mance Raider was a Nightswatch and spurned it to be with the Wildlings, John's interacted too much with the Wildlings and aside from Tormund, is essentially the defacto leader.)