If you have a week, this is the South Africa itinerary that wastes the least of it. Seven days split cleanly into three nights in Cape Town and three in a private Big Five reserve in the Eastern Cape, with one short flight between them from Cape Town to Gqeberha. Nothing on the route calls for antimalarials, and you change hotels only once.
The Eastern Cape reserves are smaller than the Kruger and fenced, stocked through careful reintroductions, and that shapes the experience honestly: lion, elephant, rhino and buffalo are regularly seen, while leopard is scarcer than in the Lowveld. In return you get landscapes the Kruger does not have, with thicket, Karoo scrub and fynbos in a single reserve, and a mild climate for most of the year. The Eastern Cape region page compares the reserves, and malaria-free safaris sets them against Madikwe.
Why this route works
Cape Town comes first because the nonstops from the US land there, and a city start is the kindest way to absorb the time change. The Eastern Cape is the closest Big Five region to Cape Town by air: about an hour and a quarter to Gqeberha and a short drive to the reserve, against roughly two and a half hours of flying to reach the Kruger, where antimalarials are recommended. Three nights in each place is deliberate: in Cape Town it leaves a spare half-day for Table Mountain’s weather, and in the reserve it gives you five or six game drives. Driving to a reserve near Cape Town is possible, but those reserves are small, and safari near Cape Town explains why the flight is usually worth it.