Francine, I wanted to reply here a couple times. Every time I think I know my favorite, I realize that there is another I enjoy as much.
I was going to say favorite peacock was Aulonocara Baenschi. I have had groups and a couple very handsome males in the past, and I've always considered the Benga my favorite. However, since, I also enjoy Aulonocara Lwanda a great deal. And then there was my wonderful strain of Aulonocara Jacobfreibergi "Ottter Point" that I had for years.
I guess I can't pinpoint a peacock.
However, I am pretty sure that my favorite haplochromine (not including the peacocks) is the Sciaenochromis Fryeri. The true "Electiric Blue" is simply unbelievable how it creates liguid metal blue color.
But then there is....