It would be in the best interest of the series to have Neji, Chouji, and Kiba to die; but if anyone was to die, I'd have to pick Chouji. Even though he's my favorite character, his death would change Shikamaru in such an interesting way. He may start to hate Sasukie for the death of his friend. If Neji died, we still have Hinata who could become even more inspired to get stronger, to fight against her fate. I don't wanna kill off Kiba because I like Akamaru and don't see how it would help the growth of characters as much as Chouji's and Neji's death. We don't really have a story behind Kiba.