It's just happens that his opinions seem to largely shared by other works about Soviet Union during Stalin. Such as the other book mentioned. It seems to be more fastidious with sourcing the claims too, so it might be more to your liking in that respect.
I wonder why books published by an Anticommunist country that went through a decades long scare would have anticommunist grifters with anticommunist opinions. I am also curious why said anticommunists also happen to be islamophobic, pro-NATO, Zionist, pro-Imperialism, and have ties to the Military Industrial Complex.
I was under the impression it was the claims we were discussing, which Khlevniuk's book seem to support, not what or who deserves our respect. For that reason it might be worthwhile to check that out too. Totally up to you of course.
Respect, as in accept the opinions. Nothing you have shown has supported the idea that Stalin could not be opposed, and was not opposed, nor that he was all-powerful.
Power. But for meaning of the word, I'd just go with something like https://en.wikipedia.org/wiki/Dictator. Fair few mentions of Stalin there, but definitely second to Hitler.