Define moderate bankroll... Most of the hot spots in Brazil are mad expensive these days (Rio, Sao Paulo, and Florinapolis), especially if you want to live in a hip neighborhood like Ipanema. I was in Rio about 3 years ago and just got private rooms in hostels, but you might be able to find a decently priced apartments in a more middle class area like Copacabana or Botafago. When I was there I went with some guys from Sao Paulo to check out some other neighborhoods a little farther out which weren't quite the most happening parts of town, but were clean, safe, and still had nice neighborhood cafes and bars, can't remember the name though.
There seems to be some racial divisions, mostly based on class stratification, but I'd say as long as you aren't shooting for rich upperclass white Brazilians you should be able to pull black and mixed (mestizo) women with no problem. I've never been but maybe look into the North East, Natal, Recife, Salvador, etc. There's a bit of intel on Belo Horizontal and Vitoria, which sound like they are absolutely stacked with hot women, but might require more time, Portuguese, and social circle to have a good shot.
There seems to be some racial divisions, mostly based on class stratification, but I'd say as long as you aren't shooting for rich upperclass white Brazilians you should be able to pull black and mixed (mestizo) women with no problem. I've never been but maybe look into the North East, Natal, Recife, Salvador, etc. There's a bit of intel on Belo Horizontal and Vitoria, which sound like they are absolutely stacked with hot women, but might require more time, Portuguese, and social circle to have a good shot.