Think that your best/cheapest options would be either direct to London/Paris or to NYC and then to either London or Paris.

Not sure that I would want to do a non stop from west coast to east coast and then a non stop from there to J'berg. That would be tough to say the least.

But it will add another day to the trip as a result. But if you are completely miserable for the trip then it might not be worth it --- that is why we did the London, spent the day, then the flight to J'berg from London. That really helped -- just the time change alone is major and we were already on the east coast.