1) Let's take for example Colombia: it's reliance on coffee has sometimes caused it problems because when in a given year the coffee harvest world-wide was successful, the selling prizes for cofee were low, which potentially lead to a poverty of the farmers. Because of this, Colombia has a number of organisations that try to help its farmers in harder years.
2) Without the conquest, it is likely that the indigenous languages and religions would still be practiced today and that the region would have a greater diversity