I was so mad that Zabuza died SOOO early in the series. Also, Haku died too soon as well. They are both strong and it is too bad they died so early in the show like that. Kimimaro died too soon as well, but then again if there was never a fight with Rock Lee and Gaara, he would died eventually because of his illness.
By characters, does that include people who died before the series and have been referred to in past tense? Or Characters involved in the main timeline?
Sasori of course but he did get 8 episodes of fighting. Itachi I wish he didn't die. and Not a literal death but figuratively Neji (his role in shippudden died so quick)
i agree about zabuza, he did die too quick. he was one of my favorites. haku could do jutsus with just one hand, he would have been an outstanding ninja. umm i think orochimaru died too easy. i know he was sick but he could have had a fight like one with the hokage, something epic. cant believe he was the first sanin to go. what a shame. and as my name has it kimimaru kaguya shouldnt have died. if he had been cured he could have been a great asset to sasukes team.