There is a thread by CA on promotion elsewhere on the ORG.
IMO you seem to get more gov's (by adoption etc)to maintain about a 50-75% ratio to your provinces.Also captain promotion seems easier if you have a low gov/town ratio.
The best way to bribe for govs is to find low star ones they are the cheapest, then you send them for training or give them a retinue etc.
I usually try to bribe the left over govs of defunct factions , I suspect(but don't know for sure)that they are cheaper then. I did get one 7star rebel general for a basement price I think of about 5-6k from memory.
I've never got over about 80-90% gov/town ratio, ? anyone have more govs than towns?
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