This is a question with an immense sprawling answer.

“What economic policies were pursued by 6 different countries over a total of hundreds of years?” can’t be answered in a forum post.

Not trying to be unhelpful, but the question is so big it’s hard to do it justice otherwise. Some things that come to mind:

• In 1922-24 Lenin reformed the monetary system. It was a dual-currency system chervonets (gold-backed, for nationalised market) and sovznaks (private markets, more like fiat money)

• Stalin: “In 1921, when we introduced NEP, Lenin again raised the question of the possibility of the victory of socialism, this time in the more concrete form of the possibility of laying a socialist foundation for our economy along the lines of NEP. You will recall that when NEP was introduced in 1921, Lenin was accused by a section of our Party, especially by the “Workers’ Opposition,” that, by introducing NEP, he was swerving from the path of socialism. It was evidently in reply to this that Lenin repeatedly declared in his speeches and articles of that time that we were introducing NEP not as a departure from our course, but as a continuation of it under the new conditions, with a view to laying “a socialist foundation for our economy,” “together with the peasantry,” and “under the leadership of the working class” (see Lenin’s ‘The Tax in Kind’ and other articles on the subject of NEP).”

• Lenin’s New Economic Policy (1922-1928) used the concepts of profit and incentives. Autonomous enterprises were not nationalized, but instead placed under the guidance of the Supreme Soviet of the National Economy, with the plan to group them into “trusts” based on production chains or geographic proximity.

• After the NEP, 1930-65, things got more centralised under Gosplan, then the Kosygin reform happened in 1965. In September 1962, Liberman wrote “Plans, Profits, and Bonuses” in Pravda, arguing that incentives and the profit motive were required. “What is profitable for society should be profitable for every enterprise,” he wrote.

The first Kosygin reform:

1. Enterprises as the main economic unit
2. The system of policy targets was simplified, in favour of independent enterprises
3. Enterprises were allowed to set their own stock, reïnvest profits funds in production, arrange contracts with suppliers, etc.
4. This was to be done with profit calculation (рентабельность)
5. Pricing: Wholesale sales prices would be recalibrated to reflect costs and encourage economic efficiency

Industries were transferred to the new system bit-by-bit, beginning at 1966, and by the end of 1967 most of the Soviet economy was using the reformed profit system. Results: The economy grew more in 1966–1970 than it did in 1961–1965.

Kosygin was a busy guy, launched wide-reaching economic reforms in 1973 and 1979 as well, but the first was the biggest.

East Germany: After the death of Stalin, the New Course was implemented to raise consumer goods and relax the terror. The New Economic System (not the NEP) was introduced by Walter Ulbricht in 1963 to replace the Five Year Plans which had been used since 1951. Then in 1968, that was replaced by the Economic System of Socialism, which similar to the Russian stuff, allowed factory autonomy (including worker-management), and market pricing, and profit as a metric.

Communist Hungary: An interesting economy. Failed to collectivise at first (under Mátyás Rákosi), then succeeded under János Kádár who declared success in Feb 1961 (I’m citing Nigel Swain’s Collective Farms Which Work? from 1985). The ‘New Economic Mechanism’ was announced 1966, launched 1968 (you’re seeing the pattern now). Hungary in the 1980s had a higher ratio of market mechanisms to central planning than any other Eastern Bloc economy. The reform is considered as “the most radical postwar change” of any Comecon country. [Granick, David. The Hungarian Economic Reform. World Politics, Vol. 25, No. 3. (Apr., 1973), pp. 414-429.]. This reform included market pricing, profit-calculations, and freedom for firms to make contracts. Hungary was anecdotally the pleasantest Soviet country, with products on the shelves. See also Hare, P.G. Industrial Prices in Hungary Part I: The New Economic Mechanism and Nigel Swain’s Hungary: The Rise and Fall of Feasible Socialism

Cuba: passed 1500 laws passed in the first nine months after the revolution, designed to get the poor on-side: things like halving rent for renters. Castro: “the owners of the lands we intend to distribute shall not be robbed; they will be compensated. They will be paid in government bonds, payable in 20 years, which will produce 4.50% interest yearly”. Cuba (to today) has the Libreta (Libreta de Abastecimiento) which is a ration-book for basic consumer goods at highly subsidised prices. Cuba has two kinds of farm: the Cooperativa de Producción Agropecuaria and the Unidad Básica de Producción Cooperativa. The CPAs have more autonomy from the state. The UBPC (created in 1993) are state-owned. The CPA are like worker coöperatives, with vehicles collectively owned for example. Empirical study of CPA performance

China:

• Cheremukhin, A., Golosov, M., Guriev, S., & Tsyvinski, A. (2015). The Economy of People’s Republic of China from 1953. doi:10.3386/w21397

• Deng’s Reform and Opening Up of the 1980s reverted to the system that existed until 1966/the Cultural Revolution, people tend to forget that.

• Government stats show collective enterprises are only 0.5%

• Hu Jintao and Wen Jiabao may have been less pro-market than Deng, were more egalitarian and populist (see Naughton, Barry; et al. (2008), “A Political Economy of China’s Economic Transition” in the book “China’s Great Transformation”). They increased subsidies and control over health care and increased funding for education and halted privatization

• In China now, 40% of the economy is state-owned enterprises (SOEs), which are not to be confused with centrally managed state bodies. They’re firms subject to market forces; SOEs can compete with other SOEs, unlike Soviet bureaux. Compare the NEP period under Lenin when 70-77% of the economy was centrally owned. See Li-Wen Lin, Curtis J. Milhaupt, Bonded to the State: A Network Perspective on China’s Corporate Debt Market, Journal of Financial Regulation, Volume 3, Issue 1, March 2017, Pages 1–39, https://doi.org/10.1093/jfr/fjw016 (39 pages)

This doesn’t even begin to scratch the surface of your question. It’s like I was asked "“What events happened in the world 1600-1700?” I just don’t know where to start. Maybe someone can chime in with book recommendations.

Things to look up include Gosplan, Đổi Mới, Lenin’s New Economic Policy, the Reform and Opening Up, etc.

Some books:

• Economic Problems of Socialism in the U.S.S.R, by Stalin
• Everything Was Forever, Until It Was No More: The Last Soviet Generation
• Murrell, P. (1991). Can Neoclassical Economics Underpin the Reform of Centrally Planned Economies?
• Otto Neurath: Economic Writings Selections 1904–1945
• Socialist Economic Development in the 21st Century: A Century after the Bolshevik Revolution
• From Commune to Capitalism: How China’s Peasants Lost Collective Farming and Gained Urban Poverty
• Deng Xiaoping and the transformation of China
• Socialism with Chinese Characteristics: A Guide for Foreginers, by Roland Boer
• Build Socialism With Chinese Characteristics, by Deng Xiaoping
• The Transition to Socialism in China
• The Transformation of Chinese Socialism
• How China Escaped Shock Therapy: The Market Reform Debate
• China’s Great Economic Transformation
• Alberto Gabriele - Enterprises, Industry and Innovation in the People’s Republic of China

If you’re interested in a straightforward English language account of life in the GDR, I recommend “A Socialist Defector: From Harvard to Karl-Marx-Allee” by Victor Grossmann, who defected by way of crossing into Soviet occupied Austria.

He addresses the perks (price fixed goods (at least staples), cheap public transport, the position of and benefits to the worker) and what could be considered drawbacks by western readers (Stasi, press freedom, limited travel opportunities, industriality of the region) in a fairly evenhanded manner. It’s been years since I’ve read this so I might be a bit off base.

A good companion piece is “Stasi State or Socialist Paradise?” for a more analytical “overview” rather than the perspective of one man.

Both of these works deal with the end of the GDR and it’s bleak.

Class theory and history: capitalism and communism in the USSR by Resnick and Wolff