been to Brasil? we want your advice

hi you all

we're now in Rio. it's really nice, like a large european city. only thing is its REALLY EXPENSIVE. we're happy for the brasilian economy, but from a backpacker point of vuew, this Real isn't funny. people here say argentina is a lot cheaper. i hope so.
anyway, our plan is to go to the Iguasu falls on the argentinian border. the only thing we don't know yet is whether we should stop somewhere on the way there. if not, then we'll just head there (24 h bus) and then Argentina. we don't really want anymore beaches - had plenty of those over at mexico, as i guess you must have noticed by the pictures. so - the only question is - is there anything interesting to see in brasil here on west, on the way from rio to iguasu, whithout going further north? (no beaches please). we heard great things about Salvador, but its a loooong way up north (24 h) and it doesnt seem like it's worth it as we're on our way to argentina.

we can't get any meaningful info from the israelis here - they're all here for the beaches and they're all so "tranqilo" and "zormim" that a direct answer seems too dificult to ask for.

friends, i guess since you have a couple of years in South America among you, your experience will be much more usefull than the info in the books. so... i'd really appreciate any advice - here or via email.

Obrigado !