Not a bad start.
Its more about the water chemistry requirements of the different types of cichlids than it is about the ability of the fish to get along or not get along. Africans have very different water requirements than New Worlds do. Keeping them together is very stressing for one type or possibly for both depending on how you keep the water chemistry, and therefore the fish can be much more susceptible to diseases and water stress issues.
Additionally, as the Africans get bigger, you are going to find that you need more rock/hiding spaces.