Lots of very deserving civ missing from that list because they are little known to the average westerner. I see the drive for Asia worked in getting the Indonesians, Khmers and Thais included, but Africa is still left alone...
A rapid look at civilizations that could be considered for AFrica
Ethiopia - that's not even an option, it's a MUST have.
Ghana (Wagadugu), OR Mali, OR Songhay - any of these three, since they were basically "successor" of each others (somewhat like how the "Greek" civilization is actually a succession of the various civilizations of greece, from Athen to Macedonia). Heck, at the heigh of Songhay power, their empire encompassed an area larger than Europe, an empire second in size (as far as my sources are concerned) only to the contemporary Mongolian empire. They had control of an area stretching from Morocco to Cameroon, going inland into Mali and all the area south of the Sahara (and controling the Saharan Oasises), and controled the rich trade in salt and gold on the western end of the desert route. They also controled the legendary city of Timbuktu.
I mean, at its greatest extent their empire was nothing short of being as much of a great empire as Macedonia, Rome, China and so on. These three are included in the game, why not the Songhay empire? (or Mali, or Ghana, since Macedonia is included as Greece).
One may also be willing to think of a Swahili "civ". Even if they were not a united country, the Swahili kingdoms controled much of Africa's east coast and much of the trade in the Indian ocean in their time. Mogadishu, Mombasa, Zanzibar, etc - all cities that still dots the eastern coast of Africa as far down as Zimbabwe to this day.
The addition of Swahili in the south-east, Ethiopia in the middle and Songhay in the west would certainly make the whole game far more interesting in Africa on the RW map than simply "Oh, hi, we got 95% Zulu control, 5% egyptian control, and most of egypt is in Arabia".
In fact, these are most definitely on my list of new civs for the modpack I'm working on. And yes, I've been researching ancient Africa lately for this very purpose.