These arguments look very similar to the rejection of institutional constraints that some anarchists have. I got the impression that you don't actually want an economic system, in the sense I think of it: a collection of people playing societal roles and forming institutions.
So it's no surprise that you find the whole thing irrational and unjust.
Hahnel claimed that humans are social, in that we build social institutions and cooperate within them to take care of our needs and desires. (Certainly not just economic ones, but also for procreation, etc.) Of course, we're more than just our social selves; we're also self-creating and so on.
So the question is, if we happen to like building social institutions, what do we want from them?
In case anyone's interested, here's a snippet of his argument:
"Throughout history people have created social institutions to
help meet their most urgent needs and desires. To satisfy our
economic needs we have tried a variety of arrangements –
feudalism, capitalism, and centrally planned "socialism" to name a
few – that assign duties and rewards among economic participants
in different ways. But we have also created different kinds of
kinship relations through which people seek to satisfy sexual
needs and accomplish child rearing goals, as well as different
religious, community, and political organizations and institutions
for meeting cultural needs and achieving political goals. Of
course the particular social arrangements in different spheres of
social life, and the relations among them, vary from society to
society. But what is common to all human societies is the
elaboration of social relationships for the joint identification
and pursuit of individual need fulfillment.
"To develop a theory that expresses this view of humans – as a
self-conscious, self-creative, social species – and this view of
society – as a web of interconnected spheres of social life – we
first concentrate on concepts helpful for thinking about people,
or the human center; next on concepts that help us understand
social institutions,or the institutional boundary within which
individuals function; and finally on the relationship between the
human center and institutional boundary, and the possible
relations between four spheres of social life."
[...]
"Why must there be social institutions? If we were mind readers,
or if we had infinite time to consult with one another, human
societies might not require mediating institutions. But if there
is to be a 'division of labor,' and if we are neither omniscient
nor immortal, people must act on the basis of expectations about
other people's behavior. If I make a pair of shoes in order to
sell them to pay a dentist to fill my daughter's cavities, I am
expecting others to play the role of shoe buyer, and dentists to
render their services for a fee. I neither read the minds of the
shoebuyers and dentist, nor take the time to arrange and confirm
all these coordinated activities before proceeding to make the
shoes. Instead I act based on expectations about others' behavior.
"So institutions are then necessary consequence of human
sociability combined with our lack of omniscience and our
mortality – which has important implications for the tendency
among some anarchists to conceive of the goal of liberation as the
abolition of all institutions. Anarchists correctly note that
individuals are not completely 'free' as long as institutional
constraints exist. Any institutional boundary makes some
individual choices easier and others harder, and therefore
infringes on individual freedom to some extent. But abolishing
social institutions is impossible for the human species. The
relevant question about institutions, therefore, should not be
whether we want them to exist, but whether any particular
institution poses unnecessarily oppressive limitations, or
promotes human development and fulfillment to the maximum extent
possible."
-- Robin Hahnel, _ABCs of Political Economy_
Tayssir