CMMAP said:
Your suggestion could work, but what to do about major side characters like varys or littlefinger? It is tough to integrate them without beeing killed, they would become just background characters.

Well, if Season 7’s Story is left mostly unaltered, then Littlefinger would already be dead. But I’m not sure about Varys. I suppose he would have served most of his plot purpose already by getting Daenerys most of her Westerosi allies. And if she is crowned as a good Queen for Westeros in the end, then his goal of “serving the realm” would be fulfilled as well. Then he could just fade into the background, still alive, without his “plotting against Dany” plot.