I am not sure why this thread was made to be honest, I mean the manga can go on for as long as Kishimoto would like it to, its all in the imagination which we can all say that Kishimoto is great at coming up with top shelf manga and anime.
Madara will have more than enough allies to assist in his plot against the world, Kabuto who will somehow control Orochimaru or be rendered helpless by his spirit is still brewing up some phonk he's just waiting for his time to strike, he is a very capable and intelligent nin so we have to expect big things from him in the future.
I really think that the original Akatsuki were in place to help the manga develope into something incredible, so far all the deaths of the Akatsuki have helped mature the younger nin who will be taking over the next generation. But their will be more powerful nin to replace them or I would hope there will be cause I wouldn't have it any other way.
Korunai is prego, Konohamaru is still young and will likely battle Naruto for the Hokage spot. Sakura, Sasuke,The Byakugan possibly playing a larger role than it has in the past, Danzo, The 4th ninja world war, Kushina Uzamaki, Naruto bringing Sasuke back or not. Am i sounding redundant yet good, not be snarchy but there is still a hella of a lot of manga to be told not to mention new ideas for the future as the manga develops further.