Many African countries, 40 or 50 years after independance are still unstable and not worth the effort of visiting. It is a sad reflection on how these countries are ruled, and, although many blame the colonial masters of the past , mismanagement and corruption do not reflect this.
Here are some countries you should avoid traveling to--with great caution or at your peril.
Guinea-Bissau-President Viera has been assassinated. Country in turmoil. Avoid.
Zimbabwe-Victoria Falls may be attractive but Mugabe has killed off most tourism with his inhumane leadership and useless currency. Try the Zambian side instead.
Equatorial Guinea: Avoid --a corrupt leader and unwelcoming military will make your visit most unpleasant.
Angola--If you can put up with over-officious airport officials, the country has much to offer. However the country still does not understand the value of tourism so expect a military State attitude..
Somalia--you're right--stay away.
Ethiopia--Addis Ababa is more civilised than we think but avoid traveling too far from the city.
Nigeria--a country full of corrupt thugs and muggers. Traffic horrendous. Stay put in your hotel.
Democratic Republic Of Congo--Don't even ask.
Republic Of South Africa--a beautiful country with advanced road systems and great hotels. Just don't walk around the streets at night, The cities are a haven for muggers, hijackers and thieves.
Madagascar---Beautiful island. In turmoil at present. Avoid until stability returns.
North Africa presents few problems for the traveller provided you have the correct visas.