What if provinces with nationalism on them also gave a significant amount of attrition, but we also upped the amount of -unrest that stationing troops in an unruly province gave? This could also be partnered with buffing harsh treatment back up by decreasing the amount of attrition suffered simulating a large crackdown on the province. This would go to better simulating why many provinces were hard to keep control of through the centuries and and sap the resources of an occupied power moreso than 1 or 2 pitched battles with rebels every few decades would. Thoughts?