I’ve seem other people state that Mueller was illegally appointed because he was supposed to investigate collusion, which is not a crime. Special counsels are only supposed to investigate actual crimes.
In the end, Muller is a tool of the DC Swamp, which is trying to expel Trump from the Body-Politic for not being one of them.
Yes, that’s another great point that you just made. The fact that Rosenstein appointed him at all, with no actual evidence of an underlying crime, is a violation of the Special Prosecutor statue as well. As usual though with any legal argument, “it depends one the judge” and I wouldn’t be surprised to see some of this end up in front of the Supreme Court.