We did the entire Lake Superior Circle Tour two years ago. I have a 5th wheel and another friend followed us around in his truck camper.
Grand Marais was great - huge camping area, but book in advance.
Don't miss Thunder Bay and the peninsula that juts out into the lake and looks back on the city. There's an overlook that should not be missed.
Pancake Bay on the east side is a wonderful park and the Voyager's Cafe is a great place to eat.
The Provincial Parks are crowded in the summer, but we were always able to get two sites if we booked a few days ahead.
Bring LOTS of extension cords. In one park we needed 100 feet of cord to reach the outlets!
If you're doing the Upper Peninsula of MI part of the loop don't miss Copper Harbor.
Here's a great Planning tool: https://superiorcircletour.com
Ron and Joyce in Florida