A huge part of the Soviet period before Stalin was the civil war and minimal efforts to do anything other than fight it ("war communism"). After that you got the NEP and things going traditional.

Stalin pushed classical and actually within the soviet union Stalinst buildings were considered the best. These are called Stalinka.

Khrushchev embarked on a massive post-war building campaign in an effort to improve living conditions within the USSR by providing millions of new housing units.

These were modernist mid-rise and high-rise buildings and were designed for mass production and efficiency above everything else. These were regarded as considerably lower quality buildings than the Stalinka and were called Khrushchyovka. The Krushchyovka were the classic "commie blocks."

Stalin was notoriously conservative in most things. I mean, the guy banned abortions, criminalized homosexuality, and re-instituted paid high school.