For Stalin, the CIA didn’t think him a dictator.

I’m once again nitpicking on this because it prodigiously bothers me: the CIA collected and compiled comments from an informant. This is the nature of the document you have linked, not their opinion on the matter, not a statement from them, nothing of the sort.
Please, you have a bunch of books from reputable historians to mention and take quotes from, stop using this “unevaluated” information report as a proof of the CIA thinking this or that.

Edit:
Here’s what they had to say about “stalinism” two years after the linked report in an analysis (Titoism and Soviet Communism):

This term is used to denote the teachings of Marx, Engels and Lenin as dogmatically interpreted by Stalin, and as imposed by him on the International Communist Movement.
The term denotes in particular the theory and practice connected with Stalin’s personal dictatorship – “one man rule” – over the CPSU, the Soviet State, and – under the guise of “the leading role” of the CPSU – over the International Communist Movement as a whole.

As a matter of fact, the CIA did think him a dictator at the time.