Make wounds last longer. I spent one week travelling to a neighbouring realm so I could stab a 70 year old duke, who was also ruler, general and judge. The duke recovered before he lost his city, before a different ruler, general and judge could be elected, and before I could even return home. I wasted more than triple as much time travelling as he did in his coma. Needless to say, I switched back to warrior class after that incident.
This depends on how deep the wound is. Sometimes old nobles are down for at least a week.
