And regarding the "murder rant video" I think it's completely possible that he's goofing around. It seems like it was recorded around the time he met Hulk Hogan, and his repeated use of "brother" is very Hogan-esque. He's obviously out of his mind on booze and (probably) coke, but I think he could just be getting carried away bragging rather than making serious threats.
Besides that, he routinely acts almost that aggressively in City Council chamber. I did not find this video particularly shocking, but I think it may be the thing that finally starts to erode his support with his base.