It seems to me the idea of either a "base pay" or remuneration based on effort are both an invitation to trouble. I find Philippe Van Parijs argument for a universal basic income unconvincing. The pay in accordance with effort would, in my opinion, eventually to an upper class. Some people would be willing to work 80 hours a week to gain an income advantage. This advantage would eventually lead to an increase in their power. If this hypothetical person were on a board of the coordinator class they would be susceptible to being bribed. People with an income advantage would be willing to pay the bribe to be given choice jobs. The only way I see around the problem is to give all individuals the exact same income regardless of whether they work or not. This would drastically reduce the coercive power of the coordinator class. Certainly there would be a percentage of "free riders" but that is preferable to a percentage increasing their work load to increase their income and by extension their power. A basic formula would be GDP - expenses for building and maintaining infrastructure / population. Not all individuals are capable of working 80 hours. I don't mean a disability of some kind but rather some people are simply born with more drive and energy. In remunerating them according to effort I do not see a way to avoid having individuals like this from becoming an upper class both in consumption and power. Under parecon their may be societal pressures not to behave that way but it would not stop 100% of the "driven" individuals from increasing their income and power. By it's nature the coordinators who are responsible for deciding who gets to be a doctor and who hauls trash have coercive powers over individuals. Equal distribution of GDP would allow people more freedom in deciding their jobs. It would not allow a blind man to become an airline pilot but it gives no avoids the problem of the creation of an upper class.
John Thornton