1. Never make a map bigger than you have to for you'll then have to edit too bloody many cities.

The scenario I am sorta working on right now, Dual Europe, is an excellent example of that problem. For those who care, the civ list is:
Humans
Hobbits
Elves
Dwarves
Orcs
Saurs
Azracs
2. I am playing my follow up to Fictional Americas, Imperial Ambition, and it is very good for something I playtested very little myself. So far I just want to rename a couple cities, place "Nubia" and "Ethiopia", rebalance a few units (Knights are better in every way compared to Pikemen at the same price), and somehow get the AI to use it settlers to found new cities.
3. 8 civs in Civ3 = sucky scenario editing.