(1) Is he didn't make the R2 his FIRST satellite-launcher. He could have a small balloon-satellite in orbit as early as 1951. The R2 was successfully launched first; in Sept, 1949.

(2) He wasted over 3 years on the R3 rocket design [1949-1952] which was never built.

(3) He should have supported Glushko's efforts to make a powerful hypergolic engine.

(4) He should have been more conciliatory to Glushko, instead of making him an enemy.

(5) Korolev should have asked Glushko to develop a 2,000,000 Newton thrust, four-chambered
rocket motor in the 1950's. It would have been feasible for the Soviets, even back then.

(6) Korolev then should have clustered five of those 2,000,000 Newton thrust rocket-motors
to make a manned moon-rocket capable of sending a 7,000 kilogram two-seater spacecraft
to loop around the moon, as early as 1965. He would have lived to see it happen.

The six mistakes Korolev made, in MHO.