As for Sao Paulo I guess everyone has their fav places to go, these are just the ones I stumbled upon:
1. 1940s skyscraper, with some nice old-tech features.
2. Municipal market, with nice inner terrace cheapo-ish cafes.
3. Modern art, with a funny little park opposite.
4. Sao Paulo Jockey Club, very nice restaurant over looking the track.