This is an interesting tank. I think you'll have more enjoyment with more viewing space. How about a downward slope from top to bottom, back to front? It's a shame to have half of the tank to be unviewable. It sounds like you have a lot of neat little fish in there that are hiding. I used to be very interested in African cichlids myself, that was until I discovered discus fish.
Here is a pic I found:
I know that's a lot of sand but I just think it's a lot more dynamic and open. You'll also still be able to see your fish dart in a out of their holes.