and honestly, I find it hard to imagine a good game without a Capitol built in the first week with a rating of 200. There's not enough money to buy an army, and it's hard to develop the castle quickly.

A Capitol can't be built in the first week with a standard starting castle: market - forge - GM1 - municipality - citadel - castle - capitol = 8 days.
In general, strong players rarely build a municipality, even at 200%. Money is obtained from money-generating buildings/looted chests/Pandora boxes, and this is all supported by an army that is built immediately. Perhaps on some poor maps it might be worthwhile to focus on money, but only in parallel with building an army.