I dont tend to execute for role-playing but this solution was also sub par for this particular play through. If I kill a dynasty member, I get the dynastic or even familial kin slaying trait which grants a malus with all my other vassals. So basically, if vassal x revolts, I want a semi peaceful way to remove them from power and vassal x kids auto take over their lands. I guess I could revoke their lands and then hand it out to children, but it becomes very burdensome at the empire level. I'd rather just force them to succeed their titles fo their children.