- Every nation has access to the sea, merge or split nations as appropriate to make sure this occurs
- The UN security council somehow manages to keep the peace throughout the entire continent with enforced peacekeepers if necessary
- No nation has a over abundance of natural resources (Nigeria, Zaire/Congo, Angola, Liberia etc)
- The Europeans don't pull shit like Katanga
- No cold war and therefore no ideological wars
- Ex-colonisers provide free higher education and subsidise primary and secondary education in places like the Congo
- Africans themselves aren't over zealous and allow for a phased withdrawal where its deemed appropriate (in the Congo but not in Egypt)
- All nations with multiple ethnicities embark on programmes such as Brazil, Indonesia and Tanzania to create national identities (this would solve the sort of problems you see in Rwanda)
- Sudan splits in half
-Ethiopia does not become 'the Ethiopian Empire' but instead treats Eritrea with respect
My two pence. I may come back later and add more. This is just a rough starting point.