And don't make it too profitable to raid the Aztecs and establish colonies, so the game won't be a race to go oversees. I would not like it, if it was kind of a sure winning strategy to go overseas as soon as possible.
I think it's ok, if you have to thow in a considerable amount of resources to establish yourself in America and that you should feel the lack of these resources on the European theatre. So in my opinion, it should have quite balanced pros and cons to cross the sea.
Well, now here you have a good point. Why not both? Why not make it almost prohibitively expensive to cross over and make the benefits realizable after a further investment. And that benefit should be very powerful indeed. After all, Spain did become quite powerful in the early part of the era until it was knocked out of play by the combined attacks on Spanish Navy by world players (Hence the value of pirates and privateers).


But seriously, if the investment is made it should be so expensive as to detract from the european theatre. The resulting consequence is a huge boost in power. Makes sense to me.....