I build far more on huge maps, usually about 60-100 in the ancient and early medieval age. In this game phase, concerning cities, more is better. Most of them will be hopelessly corrupt, oh well, but they seize land for later resources, deny it from the AI, which otherwise would settle every little piece of ground, and let you look stronger. Meaning the AI will be more respectful.
Also there's simple math: 10 size-1 cities work on 20 tiles and all citizens are happy with only 1 luxury. 1 size-10 city works on 11 tiles and needs massive improvements and luxuries to have 10 happy citizens.
Generally: Don't listen to your Civ3 advisors... they're morons.