What were some of the major criticisms of the New Deal?
It was based on government intervention in the economy
For Libertarians the New Deal was based on a violation of the Constitution. It was based on strong involvement of the state in the economy and weakened individual liberties. Many Conservatives shared this view and the Old Right emerged as a movement of opposition against the New Deal. They also claimed it was favorable to Big Business by imposing regulations favorable to their interests(suppression of the Gold Standard for bankers for instance).
For socialists the New Deal did not go far enough in harming Capitalism. Lousiana Governor Huey Long was one of them.
Marxists criticized it because they claimed that it helped regulate Capitalism against its internal contradictions and prevent its inescapable collapse.