It's going to be like rolling the dice when you're stocking the big aggressive cichlids. No guarantees that all will get along. As others have already pointed out your current plan has some flaws. Also remember if you're going to have a breeding pair of cichlids, in most cases that means no other fish in the tank, unless you want to see the cichlids put some serious beatings on the other fish. They are very protective of their fry. Of course, any that could survive the beatings would eat said fry.
BTW, I think a breeding pair of Frontosa would be awesome in your tank. Plus young Frontosa are easier to trade/sell and worth more than many other fish.