Dramnek,
Main Entry: cap·i·tal·ism
Pronunciation: 'ka-p&-t&l-"iz-&m, 'kap-t&l-, British also k&-'pi-t&l-
Function: noun
Date: 1877
: an economic system characterized by private or corporate ownership of capital goods, by investments that are determined by private decision, and by prices, production, and the distribution of goods that are determined mainly by competition in a free market
Capitalism is an economic system not an ethical one. You can have a capitalist dictatorship, a capitalist monarchy or a capitalist democracy. The onus is on those at the top to provide for those at the bottom.
Look at church groups who, it has been statisticaly proven, handle mental/emotional care better than government bodies. Thus many western governments are increasingly outsourcing say, marital counselling services to these groups.
It is up to the society to blend capitalism with care.
Similarly Communism does not have to be a repressive dictatorship.
Look at historical Monarchies. In theory they could have been great. A person trained for the job since birth. No fear of losing the job, so no repressive or populist reactionism.
There were fantastic monarchs and many many hideous ones.
Feudalism too, out of the insecurities plaguing the dark ages was also a beneficial measure of security in theory, yet was hideously abused by those at the top.
It all comes down to the moral fibre of the individuals in power. The systems themselves are not to blame.
As such, you have to break down communism and capitalism into purely amoral economic theories. Emotions and humane considerations aside which works? Which has worked?
Capitalism has been proven time and again to enrich and sustain millions of individuals throughout history. Communism is, by your defenitions so unworkable that it has
never been able to be properly implemented.
How fragile is the system if conditions have to be perfect for it to be properly implemented?
Rather than changing the system, would not a better use of energy and time be to create moral awareness in people? Hence religions (well mine anyway

) come into play. Able to exist inside all economic systems, and capable of changing even the most evilhearted individual.