Is it easier to access Iguazu Falls from BA or Rio flying?
Iguazu Falls access
The view of the falls are different from Brazil and Argentina. You'd be wise to see both. Looking at the map you posted on Travellerspoint, I suggest you fly from Rio de Janeiro to IGU (Foz do Iguacu), then cross by land to Puerto Iguazu (IGR) to have a closer view of the falls before flying from there to Buenos Aires. Note there are two airports in Rio de Janeiro and two airports in Buenos Aires. GOL offers a nonstop flight from Rio de Janeiro to IGU. Most flights to IGU go through Sao Paulo, which also has two airports.
Thanks berner256 - which of the RIO airports does the GOL non-stop flight depart from?
From GIG (Rio de Janeiro/Galeão International Airport). LATAM also has a nonstop flight on some days, but its fares are higher than GOL's. I've flown GOL several times in Brazil.