People who admit that Maoism is the development and extension of Marxist-Leninist theory believe that:

Mao's main contribution to Marxism-Leninism was his new democratic theory, which believed that in colonial and semi-colonial countries, the working class must unite with the national bourgeoisie and farmers to overthrow imperialism and feudal forces and establish people's power. Democratic dictatorship will pave the way for socialism. Mao believed that the Chinese revolution must pass through this stage before it can reach the socialist stage. Peasants are the main force of the Chinese revolution.

The biggest difference between Mao and Stalin was not their attitude towards industrialization and farmers, but their attitude towards socialist construction and class struggle. Mao believed that socialism was not a stable and final stage, but a transitional and contradictory process that required continuous revolution and mass participation.

I think you need to read this article, especially this part:

Those who remember Marxism know that the vague central point of its theoretical edifice concerns its premise: Capitalism itself creates the conditions for the self-overcoming of the proletarian revolution - how are we to explain this? If read in linear evolutionary terms: when capitalism reaches its full potential and exhausts all its possibilities, that is, when it confronts its central antagonism (the mythical point of "contradiction") in its purest, naked form form), revolution should occur? Is it enough to add a "subjective" aspect and emphasize that the working class should not wait for "the time is right" but should "educate" itself through long-term struggle? As we all know, Lenin's theoretical "chain" about the "weakest link of the working class" is a compromise solution: although it admits that the first revolution cannot take place in the most developed countries, it takes place in a country with antagonisms . . The most serious problem with capitalist development, even in less developed countries (Russia, an island of concentrated modern capitalist industry combined with backward agriculture and a pre-democratic autocratic government), is that it still considers the October Revolution a dangerous one Breakthrough, it could succeed only if Western Europe soon experienced massive revolutions (in this regard all eyes were on Germany). Only Mao Zedong completely abandoned this model. For him, proletarian revolution should take place in underdeveloped areas of the world, among the vast number of poor peasants, workers and even the "patriotic bourgeoisie" who are in danger in the third world. The aftershocks of capitalist globalization are organizing their anger and despair. The class struggle was thus reformulated as a struggle between the "bourgeois states" of the First World and the "proletarian states" of the Third World, a radical reversal (even distortion) of Marx's model. The paradox here is a proper dialectic, perhaps the ultimate application of Mao's doctrine of contradiction: its underdevelopment (and therefore the "immaturity" of the revolution) makes a country "mature" for the revolution. However, since such “immature” economic conditions do not allow for the construction of a proper post-capitalist socialism, a necessary link is the assertion of “politics over economics”: victorious revolutionary subjects do not serve as instruments of revolution. Economic necessity, unleashing the potential for further development hampered by the contradictions of capitalism; rather, it is a voluntarist agent that opposes "spontaneous" economic necessity and reinforces its vision of reality through revolutionary terror.