[Agema]

The difference between 29k and 31k is about 7%. Assuming about 1 gold per 100 population (I don't know precisely) that would be up to 20 gold per turn difference, from 290-310gp. To put that in perspective, if you start with lots of mountains around, the first provinces you would conquer would have under 30gp per province, but a neighbour in plains would get about 100gp per province. It's also considerably less than the admin bonuses of start cities (about 30%-60%).

Changing capital start populations (and thus income) to any particular degree dependent on terrain is in my view a *really* bad move. You would virtually write off every nation who started on mountains/wasteland the minute the game started. On the other hand, a random fluctuation of 7% is little more than flavour.