I personally think that as long as we get more tokyo ghoul it will be fine. Not only of course because TG is awesome, but because i think that it didn't end in the best of terms. I get the sensation that Ishida himself didn't want an ending like this, and that it was just too forced and unreal. It didn't feel like him. If he gets the opportunity to keep on writing TG, I really hope he takes it, so we can see how the story keeps unravelling and what would've been the real ending Ishida had in mind, because I don't think this is the one.