I've played this game for a very long time and have tried many different strategies. The best thing to do is get as many villagers as you possibly can, crank those resources. Use the Spanish, they are by far the best. If there is water, use fishing boats for food instead of farms, they are more effecient, last longer, and are less of a pain. Remember, if there arent any fish, you can use fish traps. This is the important part when building an army. FOCUS ON ONE UNIT ONLY!!!! If you are using the Spanish, you can shred an army to pieces if you have conquistadors. If you try to use a combination of crap, you end up wasting valuable resources trying to upgrade them all. Another thing, never, and i swear it, never use seige weapons. They are the biggest scam in the game. Sure, an onager can take out many units at a time, but they stand no chance when an enemy is close. They also cost alot of resourses that can be used for other things. Also, seige weapons cause friendly fire, and can kill your precious soldiers. The only useful thing that you can get is a seige onager (after spending an arm and a leg), which can take out trees. Swarm an opponents city with your army, and use trebuchets to take out the buildings. Use a lot of trechs together to get rid of buildings quick.