I love answering "travel guide" type questions! If you missed Seeney Wildlife Refuge on your last trip it would be a great place to check out on your way to Munising. They have a very interesting visitor center and a really cool drive through the Refuge taking you among the various nesting pools, you may even see an Osprey or an Eagle. West of Munising the Keewanau Peninsula is both a very pretty drive and an interesting one, look up Keewanau National Historic Park which is all about when "King Copper" ruled the area. Porcupine Mountains State Park is another must see place with it's miles of hiking trails and beautiful views. A little further west is the Black River Scenic Drive (north out of Bessemer) which follows the Black River all the way to a National Forest campground and picnic area on Lake Superior. There are five (I think) parking areas with short trails leading to waterfalls, very pretty area. The Apostle Islands National Lakeshore in Wisconsin is another worthwhile stop as are all of the many Minnesota State Parks along what's known as "The Arrowhead". This is a scenic drive along Lake Superior from Duluth to the Canadian border. Voyageurs National Park is mostly a water park, canoeing and kayaking are big up there. There are a couple of mainland camping areas and visitor centers there as well as some concession operated boat tours but the bulk of the park is back country. Ely Minnesota is the home of the International Wolf Center, if Chloe likes wildlife do not miss this place. They have a lot of hands on exhibits (ever tried to howl like a wolf, it's fun) plus they have a resident wolf pack which can be observed through a series of large windows, if you're lucky your visit will be on feeding day. Road kill deer are the wolves' staple food.
About Isle Royale, you can only access it via boat or seaplane. From Copper Harbor it's a three hour ride one way or from Houghton it's a six hour ride one way. It's mostly a backpacker's paradise. Rock Harbor on the east end of the island does have some non-backpacker amenities but they are very pricey. When my wife and I have been there we've rented a housekeeping cottage so we can cook all of our own meals eliminating one major expense making it somewhat doable. Windigo on the west end of the Isle is for day use or back country use only as there are limited services there. It's about a two hour boat ride from Grand Portage, Minnesota. I just looked, Windigo does have two one room cabins but you have to bring everything with you for sleeping and eating.
Hope this helps!
Gary