Ok--so I'm really very puzzled by this plan.
You want to spend 6-8 weeks in 7-10 countries? And you think that is going to give you some sense of the continent?
What you're proposing is roughly one week in each country. And actually less when you consider that each trip is going to be a full day's travel if you fly. How much insight into a country's geography, scenery, and culture do you think you're going to get in one week?
I think you're underappreciating how big Africa is and how diverse it is. People get fooled by the Mercator Projection, thinking it's like Europe and you can just bounce between tiny countries easily. It's not.
With eight weeks, you can see maybe one region of Africa. You could do North Africa (Morocco & Tunisia), West Africa (Ghana, Guinea, Senegal, Sierra Leone), East Africa (Kenya & Tanzania), Lacustrine Africa (Uganda, Rwanda, Malawi), or Southern Africa (South Africa, Namibia, Botswana, Zimbabwe, Zambia). Don't fucking go to Madagascar, man.
Traveling overland is do-able from Zambia down to South Africa. Not particularly desirable, but do-able. But otherwise, it's really challenging and you're vastly better off flying.
I have no experience with West Africa, but can give some thoughts elsewhere.
Oh, and for the record, I think a safari in South Africa and a safari in Kenya is plenty different. But what are you interested in? Are you in for the wildlife/safari deal? In which case you want to hit up the Masai Mara in Kenya and the mountains of Uganda to see the gorillas? Or are you more interested in the cities, in which case maybe you want to do Casablanca and Cape Town? Or do you just want to see natural wonders, like Victoria Falls and the Skeleton Coast?