After Franklin Delano Roosevelt, Congress passed the 22nd ammendment, limiting presidents to two consecutive terms. This was to prevent a leader from dominating the executive office like he had, and to prevent any potential abuse or misuse of power.
Although it is difficult to say whether there were distinct policies in place to prevent the future build-up of power in such a tyrannical fashion, the tone of the government definitely changed. Instead of the government of personality that had prevailed previously, the Soviet government was replaced by a troika of Georgy Malenkov, Lavrentiy Beria, and Vyacheslav Molotov. Between the three of them, they came to more consensus decisions with the Presidium and Supreme Soviet. This post-Stalin government would initiate a campaign of "peaceful coexistence" with the West, and cut back on repressive measures. One exeption was the East German Uprising of 1953 after which Beria was charged with treason for his brutal treatment of East German protestors. Eventually, Nikita Khruschev would become Soviet Premier. He initiated a series of "de-Stalinization" measures. These measures as he explained in his "secret speech." Khruschev "condemned Stalin for irrationally deporting entire nationality groups (e.g., the Karachay, Kalmyk, Chechen, Ingush, and Balkar peoples) from their homelands during the war and, after the war, for purging major political leaders in Leningrad (1948–50; see Leningrad Affair) and in Georgia (1952). He also censured Stalin for attempting to launch a new purge (Doctors’ Plot, 1953) shortly before his death and for his policy toward Yugoslavia, which had resulted in a severance of relations between that nation and the Soviet Union (1948)." None of this sat well with Molotov, a close friend of Stalin and his foreign minister, but Khruschev's words seemed to ring true for the rest of the Presidium. Subsequently, when Khruschev's domestic popularity waned, he would be removed from office peacefully and Leonid Brezhnev would become First Secretary of the Central Committee.
Sources:
Stalin's Wars by Geoffrey Roberts
Molotov Remembers by Felix Chuev and Vyacheslav Molotov
Encyclopedia Britannica for the exact quote above https://www.britannica.com/event/Khrushchevs-secret-speech
follow up question. What, if any, affect did these measures have on Nikita Khrushchev coming to power 3 years after Stalin's death?