Could Try a Keyhole (Aequidens maroni)
Keyholes are one of the most gentle and Angels can be ok as well but I guess there note really exclusive. But its pretty hit and miss really with all Chichlids. For instance I have 2 firemouths that are extremelly passive and my Jewels are ok as well. But bear in mind you never know with Chichlids and to a certain degree "Its suck it and see" with these fish.
It also depends on the tank set-up. if you get this right with rocks and plants and correct hiding places etc. this will also make a difference to there behaviour.
Also in my experience, espeically with fully grown males. if these fish are left alone in a tank for too long they will be very aggressive when you add others as they will try to dominate the tank so try not to be tempted pruchase large/fully matured fish.
Josh.