If you are staying in Grand Marais, I would also suggest going north all of the way to the border. Grand Portage State Park at the border has a very nice, short hike to High Falls. It's mostly cedar and pine but there also are patches of really nice fall color along the trail and at the falls. 10 miles north of Grand Marais is Naniboujou Lodge which is also worth seeing. The dining room is unusual and spectacular and we always enjoy stopping for coffee and dessert.
Oberg Mountain, while not a hard hike, is definitely a hike but well worth it if you can manage it. About 1/2 mile gradual uphill and then a loop with some up and down. Around 2 miles total.
Sorry, I love the North Shore so I'll make one other recommendation. A couple miles south of Tofte is Sugarloaf Cove Nature Area. Another very short hike to a secluded cove that is very scenic.