Of course, I don't think the dossier was accurate. Its origins were always suspect (proved to be). I've said so from the beginning. I don't believe that made the investigation into possible connections with Russia illegitimate. There were several and they were rightly suspect. The Russians did try to influence the election in favor of Trump. Russia is not an ally, of course that had to be investigated. The results weren't positive for Trump so Trump and his followers did what they do and tried to discredit it completely by lying about it (well, the totally devoted Trump followers likely believed the lies).
Do I believe in the deep state theories popular among Trump supporters? I do not. Of course, there are some bad apples here and there motivated to action or biased by their political ideology (both ways, incidentally), but it's not some wide-spread issue or any sort of conspiracy by them. Take the FBI, for example. Key people in the FBI have long been Republicans. The majority of the FBI rank and file are almost certainly Republican or Republican leaning because Republicans are generally drawn to law-enforcement more than Democrats are. There is no deep state conspiracy withing the FBI to get Trump or Republicans. It makes no sense. Same with the military. I know from personal experience that the majority of those in the military are Republican or Republican leaning. However, Trump quickly decided he knows more than his military advisors (he doesn't) and disregarded their advice or treated them with the most disrespect I've even seen from a President. Trump turned on each and every Republican that didn't show total devotion and loyalty to him personally. That's not how this is supposed to work. The devotion and loyalty is supposed to be for the constitution and NOT to a President and all his whims. Regardless of personal political affiliation the vast, vast majority of the FBI and military try to do their jobs in a totally apolitical way and have succeeded in doing so, with few exceptions, during our country's history.
Mattis was one of the best SecDefs during my adult lifetime and Trump turned on him. Then Trump's loyalists did the same. That's one of the most disturbing aspects of Trump's administration and Trumpism (devotion to Trump over party or country).
Also, Trump is no leader. In addition to being able to project command presence (he can't and doesn't), leaders have loyalty and respect for their subordinates. Trump has neither for them. None at all. He was unfit for the office.
No, I don't like him. His personal character and behavior are unacceptable. He's unethical and irresponsible with criminal tendencies (the classified documents case is absolutely indefensible - and that's only one example). He's a blight on the Republican party. Other than that, he's superb.