South Africa stop off destination

We are planning a south africa honeymoon in Mid October which will finish in Capetown after doing the garden route. We will have about 4 extra nights afterwards before going home to London and would like to make the most of it. Where would be a good and convenient place to go that would offer beaches and sun for relaxing? We like off the beaten track spots. I see Mozambique gets mentioned but I am unfamiliar with it, Oman a possibility too. All suggestions welcomed.