Focus on concepts such as externalities, market failures cf. Heilbroner argued that exploitation strictly defined as the extraction and appropriation of surplus value from workers is a fundamental part of capitalism. I have to agree with Denise that a mixed economy sounds pretty good right about now. Both Nove and Kuttner have proven that socialist and capitialist idealogies, enforced independently, cannot operate efficiently and to the benefit of all society . Under socialism, discrepencies in government planning lead to an uneven balance of supply and demand which is difficult to overcome because of the complexities of any society.
Capitalist ventures tend to favor the rich getting richer rather than a distribution of capital.
As for the exploitation of workers under socialism, I am unsure. Just thoughts to add on. Denise summed it up pretty well. Nove mentions several times the concept of scale and diseconomy of size. He suggests that alienation can be due to a large industrial society, not just the economic system.