I'd love an overhaul that makes Skyrim actually feel like there's a civil war going on. A few things: alert and suspious gaurds, public executions of spies and traitors, heavily baricaded cities and towns. Spying and spy catching missions. Jarls should be opening their coffers to buy high value weapons. Food should be in short supply, many farms should be burned. Displaced populations, particularly non-Nords, crowding refugee camps. ect, ect, ect...