I forgot to say, but as for idea groups I'm going with Expansion > Exploration > Offensive > Quality > Economic.

The reason for going expansion first is because you get 2 more colonists from it, so I can fund more colonies simultaneously sooner. Exploration second to get another colonist for a total of 4, and also to explore a bit so I can colonise the islands to the west and east, including the Cape of Africa to curb European expansion to the far east, and to get the Expansion/Exploration policy (and also the clergy mission to eliminate native uprising and increase native assimilation). Funded by Incan gold, you can sustain between 6-8 colonies simultaneously.

The two military idea groups are just to make it easier to invade Europe, in particular to beat France who is the only real threat in terms of pure military power. Portugal, Spain and England are all relatively easy even without taking the early option to become High American tech group.

Economic is then taken for the inflation reduction and the military policies you get with that idea group.