I loved the challenge of conquering the world. I loved trying to figure out the right combination of responses to negotiate treaties. And also racking up huge kill numbers was fun! The sea battles were great (modeled right after Pirates!), the chariot races were fun, but the best part had to be the responses of the enemy generals. Stuff like "Your tribe wear clothes not right" by Galba of Narbonensis and "I shall rip out your lying tongue, dog of Rome!" by Vercingetorix of Gaul just rule. :D
I really liked the music, but there were only like 2 in-game songs... I wish there had been more.
Well, it didn't have a way of recording the "Record Achievements" at the end of the game. That would've been nice.
Also, I would have liked to see a greater diversity of units (Roman elephant units, archers, catapults, different types of cavalry, etc.), more flexibility of movement on the battlefields (you couldn't move units diagonally), more types of battlefields (trees, rivers, etc.), and stuff like that.
They really needed to cut down on the amount of gladiator fights! Practically every 3 years the citizens of Rome would "grow restless" and you'd have to hold a gladiator fight. That part was pretty pointless.
The Bottom Line
This is a really fun game. You should try to play it if you never have.