Naruto's answer is the best and the most realistic.
Leaving the world the way it is is not a good answer. The best one is at the moment Sasukes and Madaras. Madaras wouldn't have worked, but it was a good goal. Sasukes would've worked and would've save a lot of wars by preventing wars etc. Sasuke is more realistic because of this imo very good quote:
"People who are unable to abandon anything, will fail to bring about any change"
Sasuke was ready to kill Naruto, his best friend because he wanted to stop Sasukes revolution revolution. He even accepted being hatet by everyone in order to prevent wars and uniting mankind. He was able to abandon his best friend and affection.
Keep in mind that revolutions have brought us where we are and that a lot of bloodshed was needed. Sasukes way is at the moment the one that would have saved the most lifes, therefore his way is the most logical and best.