Okay, well I think it looks great so far!!! Keep it up!
I do think that some of the larger provinces (Sonora, Chihuahua, Tamaulipas, and Nueva Leon (maybe Coahulia)) should be divided into more than two sub-bonuses. Also, it may be a good idea to separate the inner province sub-bonuses similarly to how you would separate regular bonuses so that you can distinguish between the bonuses without necessarily clicking on the bonuslink.
As for how to make the central part, perhaps you could use an inset. Here's an example of what I'm thinking of
http://WarLight.net/SinglePlayer.aspx?PreviewMap=14152 . So the numbers can go in the larger paths of the territory, but both will show up with the colour of the owner of the territory. You don't have to do this (creator's license) it's just a suggestion.
But great job!!!