I’m not sure how the transfer of power works, I’ve seen a theory that the 3 Eyed Crow is actually controlled by the children. He calls himself the first greenseer, but Brynden Rivers is only 125 years old, and that skill goes back thousands of years I think (?) so he can’t be the first person to become the 3 Eyed Crow, and he could be under the control of the children. Maybe….. LOL I don’t know. When Bran is dreaming, he is told to fly, and below him there are spikes with skeletons skewered on them, so there must have been others before both of them, those that failed to awaken their powers and fell.
In the show, it’s hard to tell how much of Bran is left, is it even Bran anymore, or is it entirely the 3ER? It’s almost as if he is possessed. Perhaps that’s why they made the OG 3ER a nice Obi-Wan Kenobi type figure, to remove that concern. The show doesn’t give the 3ER the Brynden Rivers backstory, that would have made him seem evil.
In the book, we’ve got Cold Hands feeding Bran human flesh, which is probably Jojen’s body, ew. So I think you are right, perhaps Bran realises and defeats the 3 Eyed Crow, takes his powers and calls himself the 3 Eyed Raven instead. Crows are carrion birds, it’s not coincidence that the NW are called crows as an insult, and AFFC is all about people dealing with the aftermath of war. But even Raven’s are bad omen’s at least in Greek Myth, they are associated with Apollo, the God of prophecy, and they are his messengers. 3 Ravens together means he’s watching. I’m so far down this rabbit hole now lol. But yeah, Bran should come out with his humanity in tact, rather than as a host for whatever the f*ck is in that cave. In that video I posted, he reckons that the 3 Eyed Crow is actually trying to save humanity, and he does tell Bran that he will play a big role in defeating the others, but the 3EC will do it using any method, even very bad ones, that will have consequences as it does for all of the characters.
I’m not sure about the NK, Mel calls him the great other, he was a God defeated by AA, so the NK is probably a stand in. I kind of picture him like Sauron, some kind of malevolent entity, plus an eye. Maybe he will take on a physical form, but I don’t think he will be the NK, if anything the NK is working for him. I feel so out of my depth, I’m laughing as I type this. Actually I’ll be honest Bran’s chapters are my least favourite, now that I know his end, I really need to reread his ADWD chapters.
Oh and I totally expect Jon to spend half of Winds warged into Ghost, the prologue to ADWD had that horrible guy thinking he would die and live on in his wolf, seemed like an obvious foreshadowing. I miss book Jon too, he was a sassy bitch.