From my experience, part of the adventure of Serengeti is the drive. Fly into JRO. On the way, stop at Arusha Coffee Lodge for a great cup of coffee and some coffee to bring home. Maybe Tanzanite Experience. Found a lovely stone for my wife which we had set by our jeweler in NYC. Stop at Lake Manyara National Park to see the tree-climbing lions. At Ngorongoro I regret that my tour operator booked a less expensive lodge which was not on the crater rim. Spend the money for the crater rim. Then drive to Serengeti. Skip the "Masai Village" experience. A total rip off and you're not getting out of there without giving them $100 or more. Rather, stop at the museum on the site where Dr Leakey found Lucy. Then drive to Serengeti. On the return, possibly fly from Serengeti to JRO. Or reverse that itinerary.
I have cancelled my 2020 travel (or rather it has been cancelled for me since South Africa, Zambia and Uganda are closed). On the advice of public health experts, epidemiologists and other professionals I would avoid travel in 2020.