Among Cariocas and Paulistas there are some clear preferences. Almost all Paulistas I know choose to spend numerous weekends in Rio, while quite a few Cariocas go to Paulista sites (e.g. Daslu) to see, be seen, and blow money on Ferraris, Maseratis and fine jewels. To be fair there are excellent restaurants and other attractions in both cities.

As a general rule Rio de Janeiro is preferred fro non-work and São Paulo is preferred for business.

There may be an ever-so-slight bias seemingly evident in my totally objective comments. That is a mistake, I have no bias.

There are a number of less expensive hotel options that are still decent other than the Sheraton Leblon.

BTW, GOL flights can now be booked as DL codeshares on Delta.com for Iguassu and major connecting cities including both GRU and GIG.