Pirates

So the basics are that you start as a young pirate with no crew and a small ship and get to build you way up to captaining an entire fleet of pirate ships. You can peacefully trade, be hired as a privateer, or be a bloodthirsty pirate attacking everything before you. Ship-to-ship battles, land battles, and land-sea battles are possible(though land-sea are very difficult). You have to control inventory of food, goods to trade, and weapons. Along the way you have to keep your crew happy to avoid a mutiny, keep the various governments happy, save your family, find Incan treasure, and with a little luck-find a bride.

One frustrating thing I can think of is that sometimes on long voyages you can get trapped in a strong headwind and in can take several minutes to make progress. It would be nice if there was a fast forward feature to bypass some of this time. This is corrected in the 2005 version. The only other thing that comes to mind is that land-sea battles are virtually impossible so that it can be very difficult to attack towns on small islands like Catalina in the Western Caribbean though even there if you approach the island enough times you eventually hit it right so you can attack via land.
All in all, it has great strategy, great story, a hundred different routes to take. I spent at least an entire summer of my childhood playing this game and I am just thrilled that I have found it again. Now I just have to find a hundred hours of free time to invest into playing it again!