Mmmm... the Electric Blue is not mbuna and really needs a 70 gal to be happy, I think. If it were mine (and I have exactly the same species you are keeping!) I would go for more Kenyi females to give you the blue factor, they stay pretty much blue and are not going to be as bad as the demasoni per aggression.
Here is a picture of my tank with all three of those species you have and how they look under the right lighting, diet, water quality, etc... I have little to no aggression, and all fish display decent coloration at all times for being cheap store-bought-probably-hybrid-run-of-the-mill fish... My male Kenyis are just now starting to become yellow, and they look much different than the yellow labs, they turn more of a golden color, retain the vertical barring...