Are you wanting to start a "United States of Africa?" Africa is a very large place. In Ethiopia alone there are loads of variations on religion, every tribe having its own denomiation. Some of these religions are forceful and violent. Others are loving and kind. Determining the best religion for Africa is going to be as difficult as for any other country.
This is along the lines of what I was thinking. Africa is such an enormous continent, it would be difficult to get so many people in such a wide geographic area to all believe the same thing. More likely, they will eventually find freedom of religion (I'd like to believe every place will someday) and there won't be a single organized religion that all of the people take part in. I'll admit I have no idea what religions in Africa look like currently, but I believe there are probably many tribes with their own way to practice religion that aren't really concerned with what outsiders are trying to push on them.
