permanent hard health loss
like serious brain damage will lower your intelligence by 1% out of every 20 points of permanent damage
bad back lower your strength by 1% out of every 20 points of permanent damage
facial scars 1% perception and 1% charisma out of every 20 points of permanent damage
arthritis dexterity and agility lowered by 1% out of every 20 points of permanent damage
ways to receive permanent damage
1.ignoring injuries you have received over a week your injuries will be lost at the end of the week but half the damage will stay is permanent it will pick randomly what type of permanent damage
2.if you take injuries to your face or your head if you ignore them at all you're going to get serious brain damage or facial scars at the end of the week
injuries heal by themselves will not cause permanent damage
there's room for improvement on this idea for sure