Not only would I recommend against keeping mbuna in a tank with a less than 4' footprint, but those kenyi or cobalts are likely to kill the peacocks. Not a good mix behavior wise.
If you upgrade to a 55g, you could be ok if you get rid of the peacocks, cons, maybe the 2 unknowns, and probably the raphael.
If you upgrade to a 55g, you could be ok if you get rid of the peacocks, cons, maybe the 2 unknowns, and probably the raphael.