Zhou, like many others in the CCP, wasn't particularly interested in Communism as an ideology, but rather saw it as the most convenient way to put China back together. One may see the reforms that in OTL were implemented by Deng Xiaoping (incidentally a former protégé of Zhou's) show up 20 years earlier.
The Sino-Soviet split would have happened no matter what. China was too big to toe the Soviet line indefinitely. The split was couched in ideological terms but it was at heart a question of geopolitics. In OTL, Mao accused Khrushchev of being "revisionist"; in TTL, Zhou may accuse him of being "literalist" or whatever (in the sense of reading Marxist dogma too literally instead of adapting it to local circumstances--it's amazing how fitting the Christian vocabulary is to discuss Communist thought). Though, being a pragmatist at heart, Zhou may have waited a few more years, until, say, China had its own nuclear arsenal; in which case the split may have been ostensibly caused by Brezhnev repudiating the reforms implemented by Khrushchev.So, an even wider Sino-Soviet split?
Maoism was a convenient name tag. They'd call themselves "Guevarists" instead, that's all. Though I notice that even now you have a movement in Nepal calling itself Maoist, which goes to show that, even with Maoism being dead and buried in China itself, it can live on elsewhere.And Maoism was surprisingly exportable. What effect would be seen in a world with no Maoists in South Asia, Eastern Europe or South America?
Perhaps. It isn't a foregone conclusion.If Zhou initiates some kind of Chinese glasnost, perhaps we could see reunion with the ROC by the present day?
You know, that would be very interesting. For one thing, that would mean that the First Five-Year Plan would run its course, but the Great Leap Forward would most likely not happen. Hendryk's points are all valid. If anything, there could be the possibility of "shuttle diplomacy" to get the Mainland and Taiwan united without any significant fighting.
The situation presented is that Mao dies in 1957. Now in 1958, the First Five-Year Plan was winding down and thus the Great Leap Forward began. Between Mao's death and 1958, a Special Party Congress would probably be declared to see who would succeed Mao. Zhou Enlai gets picked, and then it goes from there. Thus, the Great Leap Forward (an idea conceived by Mao, BTW) would not have occured.
I can't think of any year exactly, but sooner rather than later, almost like German reunification.