This is all for what i said you would really need. A keep or strong hold, what it was before converted , jailers room, armory, kitchen, barracks, leaders room, dinning hall. 6 rooms right there make for a good house. Out side village had what 6-8 houses, it dont need to be a village maybe 2 -3 shops a new barracks for guards. 5-6 guards should handle a dragon and a single farm. So after that you should still have a few un burt houses to use for what ever. Make them all fully loyal and you have a dragonborn home, fit to his title. And not one he has to pay for and build him self. In midevil times, if you gained title and land you did not have to buy a home or make a home, you got the houses and or keep on the land, some soldiers for it and you didnet pay for it it was granted.