Does any one know how a port goes from very poor to wealthy?

[Alsn]

If the wealth levels of towns/ports does increase, like it seems they should going from the boni that say "+6 to town wealth per turn in the region" etc, then they do so way too slowly.

That is something completely different. The "+x to town wealth" just means that the city in that region increases its income contributed from "town wealth" by x per turn(double click on any city and check out what different things contribute to city income).

That is also what the advisor keeps bitching about whenever you raise taxes for the nobility(or middle classes if you're a republic) about "lowering taxes now and reap the rewards later" since increasing taxes will incur a penalty on total "+x to town wealth".

With regards to the topic at hand however I have also been curious about this and rarely(if ever) will a "new town emerges" ever be anything other than very poor. Not really sure what that means as I haven't had the time to check if they ever increase from being very poor(just started to understand how income works a couple of days ago).