The relative difficulty of getting into Marxist-Leninist theory is a totally valid point. Part of the issue stems from the fact that Marxism-Leninism is over a century old, and Marxism is older than that. However, using a bunch of synonyms can make it more confusing to look back on theory and understand it, it boxes us into contemporary terms that the capitalist superstructure has molded its favor. "Business owner" sounds much less nefarious than "bourgeoisie," because the former has connotations grounded in our daily capitalist experience.

This is more of a philosophical argument, though, your base frustration is absolutely valid. It's an investment to read theory, I'm not going to pretend that it's all obvious. I've been reading theory for years, and I still don't have a firm grasp on everything, just the fundamentals. I just disagree with cedeing control of language to the bourgeoisie.

As for Russia and China, Russia is closer to China than it is to the west when it comes to Africa. Russia does not have the financial capital to dominate Africa. The terms of its trade have to be more beneficial to African countries than the west, because they can't rely on financial domination to fix terms. China isn't developing Africa out of simple altruism either, it needs minerals and customers as well, but the qualitative difference between Russia/China vs the West is that the West takes everything that would normally be invested in development as profits for themselves, while Russia cannot do the same, and China has different material incentives as it needs to build up international trade and its own self-reliance to survive capitalist encirclement.

If older Marxist theory is too impenetrable, a good work I'm reading now is How Europe Underdeveloped Africa by Walter Rodney. It helps explain that trade isn't bad itself, it's the nature of capitalist imperialism that underdevelops African countries. Russia doesn't have the same tools nor resources to do so.