Honestly, capitalism would be a good system if we had just one example. Closest example is maybe Hongkong or Singapure, see http://www.heritage.org/index/ranking
The reason we have overlays on capitalistic systems seems to me to be because capitalism values the masses [people] at approaching zero, except where slavery/soylent green/organ harvesting and such is allowed.
Scenario: Humanland has a dearth of population who're not adding culturally or through labour to their pure capitalist economy - if they kill them and use them for animal feed they will both add resources and reduce outputs. Under capitalism, why not?
Capitalism starts with financial wealth and aims to increase it through competition.
Communism starts with human society and aims to support its needs through cooperation.
The later always seems to be far more reasonable to me. You intimate [I think this is what you're saying] that there has never been a capitalist economy and that this would be best - absolute market freedom - I'd like to see a communist society that didn't degrade in to a dictatorship.
In recent historical economic systems it seems this pithy aphorism is apposite:
"Under capitalism, man exploits man. Under communism, it's just the opposite." (J K Galbraith, https://en.wikipedia.org/wiki/John_Kenneth_Galbraith)