It depends on what your into, I like seeing a mixture of different species of cichla, but if your trying to breed a certain species and thats all you have in there thats cool too. As far as dithers I like large silver dollars, I love their schooling behavior and how they constantly swim, now throw in a catfish or two to clean up the bottom, and an aro up top for top water action and thats the perfect combo Imo.
What type of PB is that alone in the second picture? Me likely!
Ive done a few different species together. I like a mixed look. But I also really like a tank full of azuls(ado had a rad setup). I enjoy the bichirs on the bottom as well as a tig or some rays. Lately Pete turned me onto Geo's. I like how interactive they are and they are also good at cleaning up. An aro or 3 also look good with the bass. What I dont like is the central american cichlids mixed in w/ the cichla.