The five kages, we need a newer generation of leaders. Then Kurama (not really die, but like get taken away by the god tree) It will make Naruto have to get stronger on his own.
2 of narutos friends will die. I think sai and ino.
bee. (Pretty much all who taught naruto something have died. Even asuma)
More shinobi
other shinobi.
Old man kage. (Tschui guy cant spell)
Raikage defending bee if thats how hes gonna live.
I can see Oonoki, Kakashi and even Tsunade dying. Injuring extremely badly Sasuke, Sakura, Hinata and Naruto will go Berserk, meet Rikudou, and you know the rest.
Though, no fight seems to be prepared now, since Mugen Tsukuyomi is about to start.
Kakashi and Oonoki, there needs to be a sense of passing the torch on and I really think Kakashi needs to die in order to do that and at least one of the five kage needs to die in this war.
Well I don't think that it's matter of taste rathen being unavoidable. I believe that Gai must die after activating 8 gates. You can't just introduce a technique like that if you don't plan to use it.