As someone else said in a tag, GRRM wanted LSH to be in the story too (so much so that it was one of the few things he was vocal about in his disappointment when it came to GOT) does that mean she'll be QiTN? That's how dumb antis sound when they bring up GRRM wanting Rickon in the show. Of course he wanted him, at the time he was still thinking he'll finish the books before the show. And Rickon has an arc coming up in Skaagos with unicorns in it, who wouldn't want that in the show?
I also think that the family dynamic is something that is precious to GRRM, and Rickon as the baby brother is important!
And to be quite honest, I think GRRM would have just loved for all his characters to be in the show.
I also have the feeling that many things GRRM said are blown out of proportion. “He wanted Rickon on the show” becomes “He didn’t want Rickon to die.”
I would have liked Lady Stoneheart as well. I think she is rather creepy but I can’t wait for her to loom over Walder Frey, dagger in hand, after having killed of each and everyone...
“I match you, Lord Frey, son for a son.”
On the other hand, I don’t even want all Freys to die... Olyvar is precious. And I want him to live.