Try playing in West Africa. Portugal and Spain are so rich from Sevilla that they have *several hundred light ships* patrolling Sevilla alone, pushing local trade power to several thousand. (Plus whatever they have in the Caribbean). This leads to downstream propogation to Ivory Coast that smothers local trade power, even with virtually no local trade, and drags it all up to Sevilla. Heck, it's enough to get a noticeable share of trade as far away as South Africa.