How do I put this... it sounds too tropical and tribal for Brazil. Even if I admit it's gorgeous! (I fav'd it on youtube, never head of Uakti)
Brazil is an European civilization. They're to Europe what the American (US) civilization is to Europe as well. Certainly, Brazil, for the particular circumstances that involved the Portuguese colonisation, and the later Brazilian independence, is closer to its Amerindian roots than the US is. But still... today, according to the FUNAI (Fundação Nacional do Índio) less than 0,1 of Brazil's population is Amerindian.
Unfortunately, things didn't go much differently in Brazil than they did in the US, the result was the same (the annihilation of a vibrant culture, overwritten by the English/Portuguese culture, and the cornucopia of immigrant cultures that followed US/Brazil independence), even if the means were different.
For that reason... I don't agree with the too tropical feel of Brazil's theme. It has to be something more Brazilian, really Brazilian, something typical of what we call Brazil today (the Europeanised South American country, with its main cultural substratum - Portuguese culture - mixed in with the Afro-American, Amerindian, Italian and German cultures: what makes Brazil in 2013, and what started to make Brazil since Pedro I, really.).
So, I'd go with Heitor Villa-Lobos, the perfect mixture of all I've mentioned. And I think we may be on to something with it, as I've seen in that IGN video a Great Artist called "Heitor Villa-Lobos". They probably reached his name when looking for a Brazilian theme, I'm guessing...
Either Villas-Lobo or something from Tom Jobim, Cartola, Astrud Gilberto, and so on... I love Bossa Nova. My mother kept some vinyls at home, and I remember them since I was a kid. Musically, I think it's Brazil's greatest gift to the world
P.S - Há TANTOS portugueses e brasileiros aqui! Nunca imaginei! É excelente termos os nossos dois países representados