I really dislike black sand, so I would personally replace that, but that might just be me. I really like the “cichlid sand”, I think Carib sea makes it.
as far as decorations go, if you aren’t wanting driftwood, there are some pretty nice “Cichlid stones“ available at LFS and online. Those mixed with some river rocks from Home Depot could make a pretty cool scape/set up for cichlids.
I would recommend considering driftwood, as it can very easily transform a tank. Most of my local fish stores sell aquarium safe driftwood for reasonable prices. You could probably find a single piece big enough to span most of the tank. Mix in some rock work and you’re good to go.
Here was my version of a cheap and easy aquascape, think I used Home Depot rocks, petsmart sand, and a piece of Manzanita from manzanitadriftwood.com
Also, I apologize if I’m telling you things you already know, or things already said in this thread, I didn’t make it through reading all the posts Haha