As to unions stopping a communist revolution... I find that argument lacking in credibility. Especially since in places where the unions were the strongest they seem the most inclined to communism while places where they are the weakest are the least inclined to communism.
This strikes me as a bug being rebranded as a feature. Come on. You can do better.
One of the things that is especially amusing about the communist revolution theory that marx threw out is that it doesn't make any sense in the context of history.
Marx was quite good at analyzing EXISTING economic models but his grasp of human psychology, anthropology, culture, history, etc was not terribly good. Those that believe in a more communal life style would do well to start from scratch ideally with some people at the center of your group that understand what they're talking about a bit better. Marx and Marxist theory is generally not very credible if you analyze it with a clear eye.
This notion for example that you'll get some great uprising of workers forgets that workers have been abused far worse than that over time and while there are rebellions they don't ever lead to some communal state.
What is more, communal social arrangements have been tried repeatedly. Famously in one of the first English colonies it was tried. The name of the colony slips my mind at this moment, but they tried to go fully communal. They had a universal commons that everyone could work as much or as little as they wanted. Property rights were pretty lose. Sounded nice... only the colony nearly starved to death because there was no incentive to work. You got the same share of food whether you worked or not so why work?
Anyway, they shifted to a more traditional relationship where people owned property, worked that property, and traded for whatever else they wanted. If you didn't work... then you didn't eat. The colony was saved and ultimately became quite prosperous.
The whole communist/marxist system is at best ignorant. And so I don't especially fear it beyond being subjected to it by force by either ignorant people or tyrants exploiting the ignorance of people to build armies and subjugate people for their own profit.
Doubtless you disagree... that's super. We'll probably have to agree to disagree on that one, chum.