I think Unsworth should at least be someone the players like and respect, which would stabilize the situation for this season. Certainly no need to bring in an anti-footballer like Fat Sam.
The key is not to overreact and hire him permanently unless he well and truly bosses it. I think you have to grade him very critically, and not give him the benefit of the doubt, for the reasons listed above. No place for sentiment, because it would be a risky thing to do.