The most well run communist state was probably Yugoslavia. I can see a few things which made it more successful than other communist states: it did not cut itself off from the world as a whole or associate itself with a much bigger and more powerful communist state and it allowed its citizens more personal freedoms than any other communist state. Of course it eventually collapsed due to internal and external pressure, but communism was not ousted due to a mass civil uprising (the wars were largely due to the policy of forcing a pan-Yugoslavian identity independent of pre-existing ethnic differences). In Slovenia, which only participated in the wars for a few days, the transition between communism and capitalism happened gradually and to my knowledge non-violently over 10 or so years.