Some kind of eudaimonia metric with the whole cohort of people happy, healthy and thriving reducing the variance.
better way is regulated capitalism. Its just citizens don't stand ground when capitalists compromise regulation, and our regulated capitalism becomes not regulated.
We can't even keep laws on the books that were passed as a result of the Great Depression or Great Recession. All normal people agreed that we should not repeat those catastrophes, and yet the rules were repealed because they inconvenienced the rich people who wanted to make more money, and what they say goes.
We need a system without coercive hierarchy, and without a system of haves with power and have-nots without it.
If citizens stand ground I think we can. I consider Scandinavian socialist capitalism as success. If citizens don't care then capitalists do regulatory capture as you described.