Just like to know what people's favorites are. We don't have time to see everything in the guidebook. We do want to make time for the new Zeitz museum. What else should we see?

I highly recommend the District Six Museum.

I agree! If you have time for only one museum, it should be District 6.
District Six Museum

IMO top priority should be Table Mountain - if the tablecloth is absent, never mind about anything else up you go! And on a nice day, Kirstenbosch Gardens are terrific.

For art, other than the fabulous Zeitz MOCAA, Woodstock for top galleries and street art

The Zietz museum is the premier gallery in Cape Town. For me it i by far the best the city has to offer.

For something completely different, head to Bree Street on the First Thursday of every month. While galleries in the area open their doors for free, many pop-up galleries also appear for this event. Think artistic appreciation with a glass of wine in your hand. As the sun sets, the night quickly becomes a full blown party

District Six. I also liked Gold Museum, interesting counterpoint to District Six.

basexpatexplore: When topping a thread is is a good idea to first looks at the dates. The OP is a year old and the trip was last March.