At the moment what I want to see more is BNW versions of Kongo and the Garamantes!
I'll be releasing my Garamantes update next week (let's say Wednesday or Thursday). It'll have the updates I made for my collected mod pack, along with more efficient lua, and a minor tweak to the UU.
I haven't done any new art for it at the moment, and the initial BNW release probably won't have any new art. After I finish converting the rest of my GK mods I intend to go back and update the map and make new UU/UB icons for the Garamantes. I don't believe there's a new leader scene planned. At least, I haven't asked anyone. Updating their leader art is kind of a low priority for me at moment in between still updating my GK mods and finishing Harappa/Champa/Zimbabwe/(Mystery Civ).
Found the problem, Tomatekh's Benin mod blocks Zambezi. All fixed now.
My BNW release? I must have forgotten to remove it. I had it in GK because of a potential LUA overlap (and when I updated it we thought we would include Benin in the Zambezi pack shortly after, so it was to prevent people from activating the same civ twice).
Also, Kongo and the Garamantes should still work with BNW, we only updated the Kilwa for flavour.
Actually, I'm not sure if Garamantes as is works in BNW. Well, there's two versions of the Garamantes at the moment. My stand alone (Zambezi is actually using an older version of my stand alone) and the one in my collected mod pack. One of these uses some interface lua that will mess with GK.
Ehrmn.... Well, no one really

... We call him "Cahuachi" because that's the name of the capital, but there's no real record of a specific Nazca Leader hehe. (Pouakai and Tomaketh don't seem to mind that as much as I haha)
Actually, it does kind of annoy me, but for some civs it just can't be helped, so you have to make do.
For Harappa, I went with Went Antu, which is a reconstructed proto-Dravidian title meaning "king of the high place". I think titles in the native language (or close to the native language) are a good alternative if an actual name can't be found, so that's my usual go-to. Then I use the leader cilvopedia entry talking about the civs government/leadership structure.