I think I have been to all larger reserves in SA, Namibia and Botswana and have visited also some other reserves throughout Southern Africa.
And guess what: Kruger is not my favourite one, because of the overcrowding in the southern and central areas. Nevertheless I do visit Kruger sometimes and stay somewhere in the North.
I like the Kgalagadi TFP, the Richtersveld NP, the Tankwa Karoo, Mapungubwe, Hluhluwe Imfolozi (might be my favourite big five reserve in SA), Tembe in SA and I love Etosha and the Caprivi reserves in Namibia, sometimes I feel I have to go for a really remote place and this place might be Khaudom NP or the Central Kalahari GR.
I think my favourites are