Many of them.
Mainly Lee, Neji, Gaara, Kakashi, Gai, Bee, Temari, Kabuto, Kisame for me.
I like how Lee managed to become a ninja when everyone else said he would never be one by any chance, and i like how forgiving he is for people like Gaara, Neji who gave him hell at some point. And him being a caring person. I respect Neji becoming the second strongest Hyuuga despite being a side branch member with his skill, observation and hardwork. I like the fact that he accepted Lee's rivalry even though such actions are not a part of his personality. Gaara managing to become a kage and gaining respect of his village is admirable.
Kakashi took his past well compared to many characters. Gai accepted a total drop out as his student while many others didn't. If Naruto has Iruka, Minato, Kakashi, Kushina, Jiraiya; Lee has one and only Gai at same ground. I liked Bee no taking a shit from anyone and did not let his problems get through him and make him miserable.
Despite having nothing from birth; Kabuto made into one of the strongest shinobies and accomplished hard techniques at young age. Temari is one of the rare females who is focused on battle, strong and independent. Not to mention a solid personality. That's something not seen much in this manga. Kisame gave his life like a real shinobi for duty. That was honorable.