One thing that is wrong with it is that if you believe in rationalism you reject the cult of personality. And an economy exists to serve the needs of the people, not the other way around.
I'm not really sure what you're saying here. Certainly Rand is a larger than life personality to may Objectivists. Personally, I believe that she was the second smartest person who ever lived. Second only to Aristotle.
I think I have read nearly everything written on Objectivism and I'm very familiar with Objectivist views on Capitalism. I'm not aware of where Objectivism states that individuals exist for the needs of the economy. That concept is anathema to Objectivism.