Give it flavour!

[Darkrenown]

(Why do narrowminded countries gain more colonists? And weren't most of the colonial powers mercantilistic instead of free-trade oriented?)

I think the idea is that more people want to emigrate from the narrowminded nations so there's a greater flow of people to the colonies.

I don't know if you've looked into the colonial uprising events, but decentralisation makes them a lot more likely.

The effects of sliders, NIs and the base number and success change of colonists are all modable, so you could always fiddle with them and see if you get the results you desire.