Questions concerning governors and improving economy

[Grand Duke Vytautas]

Hi guys, I know you're enjoying this game very much, so I have few questions for ya, experts! (cause I'm quite a newbie to this game). Firstly, should I always keep a governor in every settlement? (do they improve economy or smth in that town?) Especially is it good to keep a governor, who has bad things or no at all? Or should I leave settlements on their own and go with my generals to war? Thanks.
Now about improving economy. In the small settlements (

[Ldvs]

The governors can help keep the people in the settlement under control if they have a good influence and good vertus. Put high acumen governors in wealthy cities, so that it improves the income substantially.
If your governor has bad vices (the ones that make your people unhappy and prone to rebel) then better let him out than in, there will be no governors but your settlement will run as if you put a family member with no commanding skills, nor economic etc... I play with auto-manage off so I can keep the cities where no governors are assigned under a tight control.

N.B.: cities with no leader in it will be bribed at a lesser cost...