If it were me I would do a all male mix of haps and peacocks. I like the Mbuna but they are mean (only ones I would look at to mix with the others is the yellow labs or the aciei)...Mbunas are not as colorful I think...and hide a lot in the rocks...and trying to keep the tank clean with all that rock can be a pain. Keep the decorations open so the fish have lots of room to swim...easy to clean...and jam that betty with all males. This way there is no breeding aggression and not a lot of spots for territory to build. Check out my 240 build in my sig...lots of pics and some vid of my tank. I have had the piles of rocks and Mbuna before...and much rather this tank setup 
