Like anything, there are going to be opinions on both sides. Who knows what is the right way to act? But it is obvious there is a blueprint for success regarding the greatest quarterbacks of all time. And that blueprint does not include wearing your emotions on your sleave EVERY WHERE YOU GO.
Almost all the greats have played it cool and kept their emotions in check. Sure there are some who have acted emotional, but I believe they could have been better had they been less emotional. Quarterbacking is not an emotional position. It involves clear thinking and quick, rational decisions.
I don't think Rivers will make the step to greatness without learning to tone it down a few notches. Favre is the most emotional of all the greats I can think of. But most of his emotion is positive, celebratory emotion and never included barking at fans or yapping his mouth.
Rivers would do well to study The Blueprint.