We need a HC that is willing to show he cares, show a little fire on the field. I don't mean someone like Rex Ryan that is going to act like an ***, but even John Fox could get fired up over some plays when it was game time. Rivera sits there with his arm crossed like he couldn't give a **** what happens and is ready for the game to just be over already. That's probably why the Panthers are 8-10 in games they lead in the 4th quarter, a stat that you should be winning at least a 75% clip in.
I don't disagree about a coach showing emotion -- good or bad. You see guys like the Harbaughs, Cowher, Mike Smith, etc., showing that emotion. I think I've seen Rivera lay into someone once? I've seen him get excited or run down the sideline a couple times, but he doesn't make a spectacle out of himself (which is a good thing, as you noted).
I really need to do more research into that 4th quarter stat, because I think it's somewhat skewed (like the silly "games within 7 points" stat). If you're leading by two possessions like we were today, there's no reason to think you shouldn't be able to maintain that. Like you mentioned earlier, though, a lot of that is about execution. Rivera can't get out there and make the plays for them.