It would be a ver nice twist if none of these generals were to betray Qin. Something like a misdirect but in their own way all decide to actually do their job.
Or if they planned to do it, but at a turning point decided instead to sacrifice their lives or something like that.
Civil wars are good content for stories, but the other states have some pretty formidable generals, I don't think Qin could handle an event like that...unless it already happened in the "real" history.