Sword of Damocles is most complex and advanced kingdom management mod. It does not simply add player's kingdom and lords under his command but it also tries to simulate kingdom management by adding population to fiefs, health, ability to create laws, reworking economy and adding new buildings. It also allows you to choose your faith which heavily influence your kingdom, allow you to build religious structures and eventually if you spread your faith ardently enough to upgrade your elite troops to unmatched holy warriors. You will also have to develop two new kingdom management skills, Administration and Intrigues to efficiently rule your kingdom.
I really liked wat u did on this mod ive always wanted to have mey own kingdom :D. but it kida suks that u have to attacka castle first then the nation u just attacked comes after u woth like 900 guys and u only have 50. still really good mod