In the end, Naruto will have either full control of the fox/a mix between 3 chakras (His own, Kyuubi's, and Natural)/the power to take-down Madara/or authority over a vast amount of allied ninja. This will be the war where Naruto and Sasuke will compete as main figures.
The only logical outcome to make this series more dramatic would be the capture and murder of KillerBee...as much as I hate to say it. Think first, with killerbee dead, Naruto would be the last jinchuuriki. Naruto would be the ninja world's last hope, and that will give him the motivation he needs to stop Madara's plot.
Surely Madara will find a way around the necessary capture of the Kyuubi, possibly by sacrificing Kisame once he is merged with Samehaeda, and will complete the process of re-creating himself as the Jyuubi-Jinchuuriki.
In either case, Naruto would end up the victor...in life, or in sacrifice.