I don't think he will. Too much. Maybe a SH could die....probably not though....would be too brutal
fuck. Would give Oda props if he did it, but would fucking suck, making it that sad.
Can see how he could die, but then again idk who would kill him (maybe someone undercover from marines, CP or BB) and I'm not sure how sad it would be. Definitely don't think it would bother Luffy that much. Shanks dying would make more sense if Oda wanted to hit the audience.
Only if Oda's planning for Luffy to kill Akainu, with Sabo being extra invocation of Luffy's hatred towards the Fleet Admiral, otherwise it wouldn't seem necessary to have Sabo die.