It would be more of a vacation if you saved some of the Great Lakes for another trip. Ten days just isn't enough time to do it all.
I would suggest if you haven't done Michigan to head north to the Traverse City area and take in Sleeping Bear Dunes National Lakeshore on Lake Michigan. Great hiking, museums, wonderful small towns to explore and an absolutely beautiful area.
You could then head to the Mackinac area and spend a day on the island. Rent bikes and buy some fudge. :)
Then cross the Mighty Mac Bridge and continue north to Tahquamenon Falls State Park and spend time at Whitefish Point and the Great Lakes Ship Museum on Lake Superior.
By then it will be time to turn around for home, possibly by way of eastern Michigan. Have a great trip!