Yes! Sasuke should've stayed bad and Naruto should've killed him! To me, aside from not getting Sakura, that's Naruto's biggest failure.
I can't count how many times I thought Naruto was finally going to put him down..only to be disappointed by some pathetic twisted "he's my friend" BS. Like HELLO? He tried to kill Sakura the girl you supposedly love wanted to destroy your village kill the Kages and steal your dream of Hokage?
He's worse than Sakura when it comes to Sasuke-loving IMO. At least Sakura had the balls and intellect to try to do it.
Not making Sasuke pay for his crimes was Naruto's biggest failure. Heroes are supposed to have courage and a sense of justice.