Personally, I would recommend Shogun and/or fall of the samurai. Rome 1 is a lot of fun, but there is no balance, Rome will wipe the floor with anything, no strategy needed, and once your economy gets going, it's a snowball 50 turns in. Medieval II is a lot of fun, especially once you mod it, but it's rather dated. Empire is a hit or miss, it depends on what you like (if you're big into 18th century warfare, it's fun, and the intro to ship battles is neat in its own regard) Shogun (but really, Fall of the Samurai) has a good mix of classical melee/bow combat and later rifles/Gatling guns/cannons come into play, which makes it a nice mix up. In addition, the naval battles are a bit more polished from Empire, and have some interesting mechanics. Rome II...... I'd be wary, I heard it's gotten a lot better, but it was so gutted and buggy at launch I can't recommend it.