But eventually we will need to go somewhere...it is the lack of certainty that is worrying,
Sure, but ultimately, the only certainty is (and has been from the start) your ability to go home to a place where you have either citizenship or legal residency (in your case, that's two different places). Much of the world is explicitly trying to limit unnecessary incoming travel unless absolutely safe, and this will remain the case (and possibly even worsen) for months to come. The type of travel you are considering is one that is of course perfectly legitimate in perfect time, but unfortunately very much ticks the "unnecessary" box, so uncertainty will remain till the last minute as to whether you are considered "absolutely safe" at the time of entry.
So that's basically the trade off. You get some certainty if you were to return to one of the two countries where your trip would be considered essential (US and South Africa) but where you do not wish to go for perfectly understandable reasons; everywhere else, you are a "non essential" and thus uncertainty is and will remain the rule of the game for the foreseeable future.