I doubt we'll ever see Kaneki again, though. It's kinda sour, having him become a suitcase--but it was said it was unknown what would come out of it.
A sequel would probably have a human protagonist, I wouldn't like that, unless it is Juuzo. Arima may give a surprise, though.
If the author pulls something out of this, it could be the best continuation I'm yet to see. Instead of warping up the story, he hinted another story, so if nothing comes out it will be quite a troll move.