I believe that Itachi Uchiha is the best character besides Naruto. I believe him to be the best one because he sacrificed his life in order to protect his village that he so admirably loved. He decided to kill off his whole clan so their rebellion would not bring unwanted death and destruction.
And to think he did it on one condition and that was his little brother got to live because he was the one person who he could not kill. He also lied to Sasuke and made sure that he did not know that it was the plan of the elders because he did not want his little brother to look upon the village with hatred. Throughout the whole series Itachi wanted to make sure his brother grew strong enough to where he could defeat him but he did not want to have him be consumed by his hatred and trusted Naruto to bring him back to his senses. In the end however right before Itachi died he gave the last of his power and love to his brother. Itachi was a character who loved his village so much that he sacrificed his life to protect it but he loved his brother even more and in the end could not kill off the entire clan. His love was unimaginable and his sacrifice was a great one that affected a major portion of the anime. That is whom I believe to be is the best character @tayhar18920