1)Yes there is something wrong with despising someone as an FBI agent when you tell your girlfriend you're going to stop him.
2)His unprofessional behavior was telling his mistress that he would stop Trump.
3)There is a text message from his mistress asking him to take it easy on Hillary, he agreed.
I don't know why you want to paint this guy as a model agent. He wasn't. He was extremely biased and not bright enough to hide it. He hated Trump and wanted to bring him down, he wanted Hillary to win the election by a "hundred million votes" his words. He shared all of this with his lover that also worked for the FBI in text messages on his official phone.
Stzork was fired over this.
You can keep trying to spin this any direction you want, but it isn't going to change the words he said, it isn't going to make him into a loyal husband, and it can't cover up the fact that he was driven by hate. Not political leaning, not a difference of opinion, hate. He's history, and rightly so.