I'd say, not counting the Bad Guys :
Tsunade - I REALLY want her to die, after the way Kishi built up her death only to have her be rescued at the last second, she NEEDS to die.
Oonoki - He's old, he's a relic of the old era, plus he's the one who gave Madara the most trouble and the only one alive who knew him before he was resurrected. His death would hold a lot of meaning, the passing of the torch. Only thing that makes me hesitate is that he seems to lack a viable substitute for the role of Kage.
Raikage - It would give Bee an incentive to get really serious. It would be interesting to see the goofy Bee get PISSED at someone for killing his "brother".
Orochimaru - As someone mentioned earlier, he's beyond redemption. He HAS to die, thus closing the curtain on the old Sannin era. Whether is it heroically or not remains to be seen.
Every Edo Tensei - For obvious reasons.
Juugo - Not really likely, but if anyone from Taka has to die, it'll be him. Suigetsu is too much of a goof to be killed, and Karin holds too much relevance as both one of the few Uzumaki left and as a Love Interest to Sasuke.
Kakashi - I hope not, but it's almost a given. Mentor who's starting to be bested by his students? Check. Realizes his old friend is now his arch-nemesis? Check. Seems ready to accept death? Check. Man Kakashi's like Obi-wan.
I don't think any more K12 will die, I was even VERY surprised to see Neji die. Of course the main trio is also out of reach (or except maybe, and I say MAYBE, Sakura). The Sand Siblings seem unlikely too. Gaara is a bit too close to Naruto and holds too much significance as a parallel to Naruto to die. Temari has a lot of relevance as Shikamaru's Love Interest (remember, killing love interests in pairings is a baaaaad move if you want to make money from your manga). Maybe Kankuro? But I don't recall seeing him for a good amount of recent chapters.