1) Kimimaro - Had a pretty sad and lonely back story, all he truly wanted was a purpose in life and he was pretty damn strong and hes really underrated. He would've killed Naruto had it not been for Lee and he would've killed Lee and Gaara had it not been for his illness. He's badass with a unique look and fighting style too. Hes certainly my favourite.
2) Obito - He has done a lot of crimes and has done a lot of evil and cruel things in the Naruto universe yet he isn't OP like most characters and manages to get things done through manipulation. He's pretty intelligent, wise and analytical of most situations for his age too.
3) Sasuke - I can relate with the many emotional switches he's had throughout the story, it was just one thing after another for him, killing Itachi then to find out he was actually good and loved him. Sauke became enraged, even more hateful and more than anything just confused.
4)Hinata - Her loyalty to Naruto easily earns her a spot on my list. She truely likes Naruto for who he is and has liked him from the beginning, her feelings towards him have not swayed nor did she like another guy. She liked him from the start, when he wasn't so strong or wasn't so well known plus he was a loser. I love this girl, shes certainly a keeper.