For the record, I don't think what GRRM meant for Jon was as straightforward as him killing the big bad. But I'm quite sure his resurrection, which is all but spoiled since he still haven't finished the book, will be strictly tied to the overarching theme of the white walkers and he's gonna be instrumental in resolving that conflict. He's not gonna be a sidekick to the whole ordeal, once the whole deal with the White Walkers will be over, it's gonna be clear why the Lord of Light wanted specifically Jon alive.
Not that we're gonna get the final book anyway, I still believe that eventually The Winds of Winter IS gonna be released, but A Dream of Spring? no way.