Kruger Safari and Mauritius: Should we add a few day in Cape Town?

Hi all,
Basically the question in the title.
We are planning on arriving to Johannesburg and from there we will be going to stay 3 nights in a lodge in Kruger park.
Then we are going 7-8 days to Mauritius.

Would you recommend spending a few days in Cape Town in the middle? Like Kruger->Cape Town->Mauritius. We have no issues on adding some extra days for that.

Would you say 3-4 days for Cape Town would be ok? Where would be the best place to stay? Is getting a car a must?
Any suggestion is appreciated.