I'm going to go ahead and suggest a Malawi/Tanganyika/Victoria set up. Not only are the fishes colorful, but they have personality. You can also get some catfish and some other types of fish.
You could. But unless you get the discus as adults,wait on the apistos. Juvi discus do better at a warmer temp. Adult discus can be in a bit cooler water. Apistos will do better with the adult water temp.