Although I'm no scholar of the Soviet economy, based on what I've read my impression is that it resembled a series of big box stores and corporations. Instead of locally controlled, cooperative, stores, you had a few large, generic ones whose mode of operation was dictated from above, and who sold a small number of mostly generic, standardized goods. At one time some Eastern Bloc countries didn't even have restaurants, bars, or cafes, but only collective cafeterias and dining halls owned by workers' organizations. I bet the situation was the same in Soviet Union. Farms weren't run or defined by people who had worked the land for centuries in a communal, cooperative, way, but by guidance from central tractor/fertilizer/technology stations who ran the farms like agribusiness. I'm not sure how the factories were themselves organized, or who had the power, but my understanding is that they were monolithic, megalithic, and non-competitive--except when they needed to fulfill the requirements of the plan.
A better way to organize things would be to have a communal, community controlled economy, also directed by a greater plan, but run cooperatively. The stores and factories would be owned by society as a whole, but would be decentralized and would compete with each other in a heavily regulated way. Anarchy, Left Libertarianism, Left Marxism, lend themselves to a limited market if it's kept in check, which is why the Right wingers have tried to co-opt it. In fact, Individualist Anarchists often talk about a simultaneously socialist and market based system being possible.