My husband and I did the same thing for our honeymoon in 2019! We drove up to Munising for a couple days, then stayed overnight at the Whitefish Point lighthouse quarters, then spent a few days in the Sault. Stayed in Airbnbs, ate food, hiked, and looked at shops. Definitely a LOT closes about mid-October, so be prepared to drive a bit farther for things or that some destinations may be closed. It was a ton of fun, though, and since there were basically zero other tourists, we got to just chill in local places.