I currently have two 29g tanks which I keep African cichlids in - as my water is ideal for them.
I've kept a Tanganyikan tank with Lamprologus Ocellatus "Gold" (Shell Dwellers) and Julidochromis Transcriptus (Rock Dwellers) - A sand substrate with shells on the one side and rocks on the other - the combination worked well and both groups of fish bred (I also swapped the Ocellatus with N. Multifascaitus). I started with 8 shell dwellers and 6 transcriptus - and re-homed the extras.
Recently I swapped that one to fish from Lake Victoria - I have 2 male/6 female Pundamilla Nyererei but I'll probably reduce to 1M/4F if I get aggression problems.
In the other tank I'm trying a dwarf Mbuna from lake Malawi, Pseudotropheus Saulosi. I currently have 9 of them with one fully colored male. I'd like to get down to 1M/5F but they are still a bit too young to sex.
I think as a first tank, the Shell/Rock dweller combination would work the best - and was my favorite tank for quite a while.