Since people are being rightfully disappointed about the lack of African civilizations, I think it is time for present you... the Malinese Empire!
Malinese empire
Unique unit: Farari calvary
Increases combat strenght of adyacent melee units, increased strenght when fighting next to your trade routes
The Farari or "brave men" were an elite calvary regiment formed by Malinese royalty, which acted both as a combat and a support unit, often leading and instructing the infantry soldiers below them. Consequently, it will give bonuses to adyacent melee units, and will fight more fiercely when protecting the trade routes that rightly belongs to them since afterall, Mali's business means also family business.
Unique building: Sahelian mosque
Replaces temple. +2 faith and +1 science per outgoing external trade route, doesn't have manteinance costs
Shankore was far from being the only mud mosque built in the empire. A staple of the Malinese architecture, these had a pivotal role not only in Mali's religious life, but also in the education of the Malinese popullace. That means extra faith and science, too. The dependance of trade routes further synergize with Mali's other uniques, nudging you towards a more commerce-oriented gameplay
Unique Ability: Royal cecas
+1 extra trade route to your cities for each worked salt, gold or copper resource
+2 gold to your mines located in desert terrain
The Malinese empire derived a great part of its prosperity thanks to its gold, salt and copper mines. This traduces into an inordinate amount of trade routes if you are able to get these precious resources, and a more versatile, straight to gold bonus if you happen to control desert mines, turning Mali into an economic powerhouse in the hands of players devoted to locate and control these terrains and resources.
>>> Leader: Mansa Musa
Leader UA: Musa's pilgrimage
You can buy with gold religious units and buildings
All your envoys and the envoys that you recieve will generate +100% more gold
You can buy one "pilgrimage envoy" to city states. It will automatically convert said city state to your religion, as well as grant you one extra envoy
Leader agenda: Saharan trade monopoly. Likes his trading partners, dislike those civs who possess salt, gold or copper within their borders. Will always gift a little sum of gold whenever he meet a new civ, for added flavour (!)
Mansa Musa is a hell of a personality. One of the richest, if not the richest man in all recorded history, his UA is focused not on gaining, but rather
expending all that gold that Mali's UA can get you. Bring down the balance of power and foreign economies trought generous donations, and build mosques for the hell of it, just as it happened in the real world, expanding your religion by the virtue of your wallet. When coupled with Mali's other uniques, the Malinese empire will be able to employ its extreme wealth in order play the diplomatic and the religious game like no other civ!