Did my best game so far. 90% / 3020 points at conquistador level. Finished in 1646. I kinda regret that I overwrote my savegame though, since I was generating lots of gold each turn I could probably have boosted my score by waiting to declare independance/wait to eliminate alle the Torys. I was pretty lucky and actually found 7 fountains of youth, I am used to just finding about 2-3 of them
I usually play the dutch and settle in south america. I like the map where my merchantman start in latin-america, and use this to kill of the other power which lands there (usually the spanish). I then travel south and kill the english and finaly settles with about 6 colonists. This pretty much eliminates all competition from other powers, since the last people (the french) are settled in North America and will not come and visit you.
Some tricks:
Trading with the inca capital is great, sell them tobacco (for about 1000-1200) and trade goods (800-1100). You will be able to buy 100 silver for 25/50 for 100 which is great in the start of the game. The price in europe will crash pretty fast though.
A capital can train multiple colonists to professionals, which is something I didn't know until recently. At conquistador level the incas will train expert farmers which is just awesome.
All in all this is just an excellent game - the worst thing about it is probably the unit limit which prevents you from building a 'real' america =)