I chose Ecuador because my best friend traveled there in 2010 and fell in love with this little country. In addition, the tourism is not too developed over there so you can avoid the mass tourism that you see in other South American countries.
Ecuador offers an amazing variety of landscapes and cultures. There is the highlands, the jungle, the coast, and the famous Galapagos Islands. Everything is reachable by bus, and the Ecuadorians are very welcoming and interested in you and your traveling.