I think i could slightly adjust how it all went down to be less terrible.
At the battle of Winterfell everything happens the same up to the point where Theon charges the knight king. Instead of impaling him with his own spear the knight king casually grabs the spear, throws it aside and grabs Theon by the throat. A strange icy blueness spreads from the knight king’s hand and within a few seconds Theon is frozen solid.
The camera goes to Bran and hes doing his worging thing with his eyes rolled back, but whatever he is doing seems to be straining him massively. Hes shaking slightly, blood starts to drop from his nose and ears. The knight king begins his slow walk toward Bran.
The scene cuts to John trying to sneak past the undead dragon, failing massively.
The dragon corners him and winds up to roast him. You can see the icy blue fire welling up from his throat and suddenly he shuts his mouth and shakes his head back and forth for a moment and seems to spasm slightly. He recovers, looks john strait in the eye for a moment and then turns to the path that leads to the gods woods and starts running.
The scene changes back to the Knight King and Bran.
Bran is still shaking slightly and blood still drips from his nose and ears but now has a slight smile on his face. The knight king stands in front of bran looking at him quizzically for a moment before reaching back for his sword. As his hand closes on the sword handle a roar sounds behind him. He wips around to see his undead dragon burst through the gateway and lets out a mighty breath of fire at the gathered white walkers scattering them and killing many. The dragon then runs for bit and takes off flying quickly away from the castle. Bran is shaking violently now, almost falling out of his chair, it is clear that bran is barely maintaining his control over the dragon.
John runs through the now ruined gateway at the knight king and they begin fighting. John puts up a good fight, even breaking the knight king’s icy sword but gets disarmed and the knight kings grabs him by the throat. As with Theon, an icy blueness starts to spread from the knight king’s hand but this time it does not spread far and, after a moment even starts receding. For a few frames, Johns eyes turn to a fiery purple color, as the targarian blood in his veins awakens.
The blueness is now gone and small wisps of steam start coming from the knight king’s hand, he throws john back and looks at his hand. Then Aria leaps at him just as she did in the show…
The battle of Kings Landing:
Everything goes the same up to the point where Danny is sitting there listening to the bells.
Cersie is standing there listening to Qyburn tell her that the scorpions are all destroyed, the fleet is burning and the soldiers in the city have surrendered.
She turns to him says “They will fight to the last man, there will be no surrender, and no mercy”. Qyburn says “Shall i give the order then?” Cersie nods and turns back to look at the city.
The scene changes to Danny sitting on Drogon, listening to the bells and slowly getting a bloodthirsty look on her face. She turns drogon to look at the Red Keep.
The sound of shattering glass echos through the city as dozens of small ballista bolts fly out of seemingly every window in the keep at drogon and Danny. Drogon tries to take off but is too slow and gets hit 5 or 6 times.
We then get a shot of the soldiers manning the ballista to see that these are much smaller then the ones that were on the walls and ships, to justify how drogon can takes many hits before dying.
Drogon and danny fall to the city street. Drogon hits the street hard and roars in pain as fiery blood pours from his wounds. He gets to his feet and looks for Danny finding her partially covered, and trapped under debris. Danny gives him a “F*ing kill everything” look, and drogon jumps into the air and starts roasting everything in the path to the red keep as he gets peppered with more small bolts.
We then see a large amount of blood seeping out of the pile of debris.
The scene changes to John, Gray Worm, and the army as they watch drogon fall to the street, then take flight without Danny. The slaughter begins.
The scene then goes to the Red Keep and see row after row of fully armored lanister troops in the courtyard and we learn through some minor characters, that Cersie planned all long to have the majority of their troops, the best of their troops, held back in the keep and that some of them have been subjected to Qyburns “experiments”.
Drogon gets a few good passes on the keep before crashing into one of the towers with dozens of bolts sticking out of him and blood streaming out like a river.
The scene changes to Cercie’s balcony again. As she looks out on the city, large green fiery explosions start happening throughout the city, mostly on the path from the main gate but some randomly around the city as well. We get a number of scenes of unsullied, dothraki and northmen dying to the green flames.
After the explosions die down a horn sounds across the city. The main gates of the red keep open and soldiers start working their way through the city. At the same time we see more soldiers start pouring out of random buildings throughout the city, notably, away from where the green explosions happened.
Davos and some of the northmen manage to escape, as John desperately tries to cover their retreat he gets overwhelmed, taking wound after wound, the scene cuts to make his ultimate fate unknown. The dothraki and unsullied fight to the last man, driven to a rage by the apparent death of their queen.
Jamie bleeds to dead in the catacombs after his fight with Euron.
Aria and the hound are unable to get to the keep during the chaos of the battle and are forced to take the same route Jamie took earlier. They find Jamie’s body and Aria takes his face.
Back with Cersie, Qyburn reports that the battle has turned heavily in their favor, but Drogon did manage to significantly damage the keep and it would be advisable to leave for a more intact section.
We then get, more or less, the same Clegane bowl scene, only this time “Jamie” is there to lead Cersie away as the brothers kill each other.
“Jamie” leads Cersie to an undamaged section of the castle and as Cersie comes in close to embrace him, he whips out his sword and rams it up to the cross guard into her stomach, violently twists it, then leans in close and whispers in her ear “The North Remembers”. He pulls the sword out and walks away.
The final scene of the series is Cersie on the floor in a pool of blood as “Jamie” walks away and brings his hand up to his face in the same motion we have seen before when Aria takes a face off…
What happens after that? Who the F cares, with Danny, Cersie, Jaime, and Drogon dead the 7 kingdoms have a chance to recover from the clusterf**k that they caused. The exact details of how it all happens are irrelevant.