I'm not so sure about covering magic sites. They could be hundreds of kilometres apart within the province...
Other than, well, I don't really have an opinion.
Oh yeah, I'd like to see the possibility to make a "mutating" dominion which alters the recruited unit's stats randomly within given parametres. So a units HP could be affected within the range -6 to +8.
I know it's not really relevant but the weird nation plan I cooked up today after playing Kamband would really need it to work. And magic site modding. And magic sites generating random gems.
*slaps himself -bad Nerfix, be less selfish* *sticks his head into chaos mist*