Improving capitalism is possible in the abstract. The reason it's hard to imagine is that "capitalism" is not a real thing that exists concretely. It is a term used by communists to refer to the natural state of affairs that they wished to destroy.

To see this, get two people together and try to get them to agree on when capitalism started, or even what a country needs to be considered a capitalist country. Is it merely markets? If so then the Roman Empire was capitalist. Is it stock markets? Limited liability companies? Private property rights? All of the above? Who invented capitalism? If nobody did then is does it make sense to propose a replacement or is that like trying to propose a replacement for evolved things like natural wildlife ecosystems?

Once you realize that capitalism is just the naturally evolved system of mechanisms used to coordinate any advanced economy, the problem of discussing alternatives becomes clear. It doesn't make sense to try and propose a full alternative because capitalism is only really definable as "the thing that's not communism", so it's unclear what exactly you'd be proposing an alternative to.

As a naturally evolved system, the alternative to capitalism is therefore capitalism+some minor tweak. Not a radical overhaul.

Although I would argue with you that the communist governments were socialist -- they were not, at least under our current understanding of socialism (says one person contradicting another on the internet, this is opinion, I know :)) -- you're right about the intellectual blindness about other possibilities.

I find Chesteron's distributism an interesting one, and personally really admire cooperative societies.

Do you have anything constructive to offer or are you going to stick with low effort criticism without even proposing an alternative? So far all you have are weak complaints, totally disconnected from objective reality.