it would be a mean one but a beautiful one at that.
the main thing you can go by with hybridizing cichlids is that (almost) all central american cichlids (like midas, convicts, etc) can hybridize, as long as they're similar enough that they will breed. Sometimes though the pair will look nothing alike, like blood parrots paired with texas cichlids.
South american cichlids (like angels, discus, and acaras) cannot hybridize with central american cichlids. South american cichlids cannot hybridize with eachother, so say goodbye to you ideas of angelfish crossed with discus.
They can however hybridize with anything they're related to. (green terrors can hybridize with electric blue acaras, they are both types of acara.)