Pray do keep us posted.
The problem for me as a GM was getting the motivations right for my players. Indeed a "good" PC has his agenda more or less clear. Help the kingdom, get rid of the evil-doers, wage war on demons … that kind of stuff. For an evil PC the case is less clear-cut. In danger? Run away. Overcome with foes? Run away. Too much competition? Run away.
Eventually what I did was have the PCs find a cursed castle. I added a few things to the castle so that they would have something to consider before running away and also to help me get them into a more or less stable environment so that I could develop lasting NPCs and establish a more solid ecosystem. Then, when they were finally feeling safe and their evil-doing was getting in their stride, I had their castle raided by do-gooders.
In a few levels they'll make it back to their castle and then I'll have them give it a go at being overlords for a while. Conquer a few minor cities, join a running war perhaps …
Then it'll be time to roll new characters.