If you've never been, definitely visit Mackinac island, you're so close.
Sleeping Bear Dunes national park Lakeshore is great, but it's somewhat of a hike from your destination this year, everything from Frankfort to Empire to historic Glen Haven and Glen Arbor.
Awesome beaches at Frankfort, Empire, Esch Rd, Peterson Rd, North Bar Lake etc.
You have youngsters, the dune climb, floating down the Platte River to the mouth at Lake Michigan, the old blacksmith barn and historic general store in Glen Haven.
Everything along the M119 from Harbor Springs to Wilderness Point.
Night view of the Mackinac bridge from Mackinaw City or St. Ignace.
The locks in the Soo.
Munising. Pictured Rocks boat tour, shipwreck boat tour plus nice beaches and waterfalls.
Wait a minute, I need a vacation!