We went to SA for the first time last Feb. and are going back again in Feb. for 18 days.
First of all - do not underestimate the distances between places - be prepared for a lot of driving. Best map you can buy is from a BP petrol station called South African Road Atlas. Also, beware where you buy food for the car - only stomach problems we had was from sandwiches from a local supermarket in the mountains. You should be ok if you think about where you buy.
If you stay in CT for seven nights you do not need another three in Hout Bay which is on the far side of CT but still ok for all things around CT. Do go down to Cape Point and do Boulders Beach (Penguins) on way back.
You will need most of the day and drive via the Chapmans Peak Drive which is wonderful
Addo can be done in Addo Park itself or at Amakhala Game Reserve which takes in Addo for a day anyway. It was great there with very personal service and good food and comfort - unique place . They do a three night Tuskers Safari
From there - fly into Port Elizabeth and then its 40 mins. From there you could start driving back west to Knysna or Plettenberg which is close by and also lovely - plenty of good food around
Then go via Swellendam - the long drive, stay one night and then carry on to the Winelands.
We had three nights in Franshoek and did not want to leave - wonderful food and wine and service everywhere. Going back for six nights this time! If interested, let me know and I can recommend to you. Lots of lovely B&B - no need to spend in big hotels to get comfort and service. You can see Stellenbosch, Paarl and franshoek all from Franshoek - but F. is foodie capital!
Hope this is useful
ABK
You could drive to Storms River on the way back to the Windelands - a day trip is enough without staying the night