Is it ever a good idea to have an all-evil party in a D&D game? Because every story I've heard involved the adventure falling apart.
One person in your party wants to enslave the kingdom, one wants bloody vengeance, and one just really loves skinning people alive. Why do they work together and what could motivate them as a group? And then there's always going to be someone who crosses the line into things the group isn't comfortable with. I don't see it working without a lot of prep and the PCs being built cooperatively, and even then I'm not so sure.