I think that you may be mixing up two things here: political systems and economic systems. Capitalism, socialism, and communism are economic systems. Political systems are things like monarchy, republic, and oligarchy.
I will also highly recommend Wage Labor and Capital. I had to study it in university and find that it is a good high-level analysis of the systemic issues in the capitalism. For a deeper analysis from Marx, while he is most known for communism, his magnum opus was really Das Kapital, which is not about communism.