Ok bro, you can get rid of the substrate, but you don't have to get tahitian moon sand since its very expensive. I would get pool filter sand, its maybe 10 dollars for 50 pounds and you can get it a pool store or a home depot or lowes.
Next thing, the lid you might want, you could get plexi glass to fit it, or you could go to home depot int he fluorescent light aisle and get something called eggcrate diffuser. Its a white plastic rectangle that you can cut to fit the tank.
Ok now for the decor. I understand how much it benefits the cichlids to have that much of a hiding place because the tank isn't too big, but I think the first setting was a little better. Try to give the top of the tank free swimming and the bottom intricate hiding places.
I think you have some good stuff (the driftwood, clay stuff) and I am sure the fish like to not see each other all the time, but this woudl really be a better tank for Mbuna african cichlids at the moment since there isn't much free swimming room.
Good luck, and remember to only change the stuff around to how you like it. You have to deal with it, its your tank, you make it the way you like it. We are only here to provide suggestions.