there are some people who are disappointed with Itachi and are underrating Tsunade.
First Itachi: in Chapter 552 page 8 Itachi told Naruto "No matter how powerful you become never try to shoulder everything alone, otherwise you will undoubtedly fail." Itachi recognized that he is the reason that Sasuke turned out the way that he did. BUt at the same time he acknowledges that it is through the friendship and belief that Naruto has in Sasuke that will ultimately bring change in Sasuke. He is not being a coward, far from it, he is practicing what he preaches. For a guy who told Sasuke to get strng through hate, how can he tell the same guy to be good and trust the village again? Only someone who understands the pain can convince Sasuke and that person is Naruto.
Tsunade: It is so unfortunate that Tsunade's fights have been few and far between and in those fights, it is only the one with Orochimaru where she had a role to showcase her abilities. even then she was protecting Naruto mostly. In the Pain Arch, her main concern was the welfare of the village. I only ask, who among these Kages can fight with 2 Susanno swords pierced through them and still hold their own??? Madara is awesome yes but he is a Edo, he has been taken down many times. These Kages deserve their titles. am not sure how many shinobi could have survived fighting 5 Susannos each. Never underrate these Kages.