Used it for a bit now, and it's fantastic. The yes/no choice is perfect; cities with some history keep their history, but I can bring couple of new names into the mix otherwise. Thanks for sharing it!I've thought the same thing for awhile... so I made a mod to do just that! Check it out and let me know what you think:
Resource icon
Renames old settlements using current civ city names when converting a town to a city.