Hidan strikes me as a "I know it when I see it" sort of person. As mentioned earlier, the greatest virtue in Jashinism is conviction: Hidan will be much happier with a Hazou who boldly marches forward on whatever his plan is than a Hazou who continually waffles and looks to Hidan for guidance.
Genuinely, I think we would save lives by not asking for a number here. Our goal is to make Hidan happy enough to let us leave the rest of the village in peace, which means every point we score from non-murdery sources subtracts from the number of lives we have to take before he's satisfied. If we walk in and set up some twisted death game where some of them may live but others will have to die, the spectacle may even entertain Hidan enough for us to let the majority of the village flee into the night.
Of course, that's still far from optimal to say the least and I'm fond of FS's plan right now, but if we do find ourselves going down the murder route we should ask no questions, make no barters, don't stall for time or try to appeal our case. If we end up having to murder, we do it right for the sake of all the people here we'll be able to save by play-acting Hidan's perfect slaughter disciple.