I have opened this thread at test section but a wise friend suggested that this topic should also be here.
Perhaps some people might recall, in some earlier versions it was possible to change tribute setting of kingdoms. In the low tribute option kings would get %15 production of governors and in turn governers would get %10 self production increase(for the villages inside the borders). I don't think kings tributes should be lowered however I believe governors lack the motivation to settle inside the borders, so if %10 production increase is reintroduced it might result in a much healtier kingdom structure.Yes, if one settles outside, attacks to those villages will not appear on kingdom screen and also you cannot sell stolen goods. But these things don't matter for many players and having a village with slightly better oasis bonus might seem more important even though the village will be outside the borders. Therefore, if a governor doesn't want to sacrifice some of his/her own production for a larger production bonus for king(tributes), there is no reason to settle inside, which contradicts the idea of "Kingdoms".