In Civ III they should have implemented Terrain-Specific units;
such as if most of your starting cities are bordering the sea, then the game should script to allow you to have units such as 'faster ships, longer boats, and hardier boats (the trieme has a max of 2 turns away from land before sinking)
Throught the ages as your city focus shifts, your city-specificity also shifts so you receive different special units and special bonuses throught the game.
Hopefully this will create a better-changing, more intriguing Civ IV.
I agree with your civs evolving. I agree with this and believe that it may be vital for unique civs to be agreed to by the people of Apolyton. Until then, I guess I can wait for Civ IV.
IMHO, this is a better way to implement the uniqueness of civ idea. If you have a lot of early wars, your civ tends to be better fighters. If you explorer a lot, they're intrepid. If you trade a lot, they'll be capitalist pigs . And so on. It would make more sense then just saying that the Zulus are good at war even if they were isolated on some forsaken continent for the whole game.