by SnotlinG » Fri Oct 14, 2011 1:52 pm
The income is normally randomized between 5 and 40 for the starting cities.
You as a mapmaker can affect this by editing the city.
If you set the city to a "Good" or "Powerful" city it will have more in income (but also more defence and better units). If you only want to affect income, you set the city to "detailed city standard" and then you can pick the income for the city, while you let citywall & production remain...