I'd without a doubt would make Yamamoto die, because he has no feelings (like calling Orihime a traitor knowing nothing)
And if It was someone from the "good guys" I'd choose Inoue. Don't get me wrong I like her, but because of her ability
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we know Ichigo and co can't die as they will be cured. (sorry I don't read the manga so if it actually tells about Inoue having a "curing limit" than I didn't know and will stay quiet))
or maybe not KILL but limit... y'know