Came across this fun little indie game last night called The Wager. The premise is simple. You're a pirate and there's also a competitor/evil villain, and your goal is to explore and discover stuff and essentially make more money than your competitor before the time is up. You pick up loot along the way, and any islands you find can be sold to your mainland which are then colonized. There's even chance of picking up allies. I've got a former hero Captain and a parrot along for the ride.
http://www.surprisedman.co.uk/the-wager/
http://www.surprisedman.co.uk/the-wager/