Wasn't impressed by Sao Paulo... It's worth it if you're after mega-cities, otherwise, it's pretty ugly, and not an enjoyable place to walk... Sure there are interesting museums and good restaurants, but that's almost it.

I personally would skip Sao Paulo and spend more days elsewhere. You will never regret spending more days in Rio de Janeiro. Salvador may be a better choice than Sao Paulo for a tourist.

If you are heading to SP anyways, check the latest COVID restrictions because they may close museums and restrict indoor dining (which is more unlikely to happen in other cities if I understand the current situation correctly).