Suckske dies and kishimoto can move the story forward, introduce new characters, and make it more interesting.
Suckske lives and it is the same story is has been - Naruto chasing his promise to save his friend, blah, blah, blah. That is already stale.
Either way, the New Era project has already been announced and the movie is only the beginning of that. Shueisha is not going to let go of the cash this manga is making.