Sure. Salt to your taste on my ideas to suit your own plans. I don't mind it only being a 'curse' on the bloodline itself which is a superstition either way. I like the King in the Mist concept, maybe an ancient holdover from a bygone era that one could claim the mantle of for prestige. 

Also of course he wouldn't have a vast criminal empire or anything, just contacts enough to give him some tools to make moves if needed. I'm fine with a few packs of brigands and it might even just be some flavoring to suit his personality. Maybe not even criminals now that I think about it, just pockets of like 'forest brotherhoods' that made small enclaves to shield themselves from the Mad King's tyranny and they operate as bandits and rogues. 

Would you want a character sheet?