I was born in grand rapids, so it still has a special place in my heart. But unfortunately, all my knowledge of the town is about 20 years out of date.
It almost immediately become "cool" after I left. :/
Take a cruise/walk through the heritage hill neighborhood. Lots of neat houses there.
Not sure what the current museum situation is like, but GR has always had nice ones. Including the Gerald R Ford museum.
If the gypsum mines are still doing tours, that can be neat.
https://www.atlasobscura.com/places/michigan-gypsum-minesAvoid 28th street at all costs.
Grand Rapids has a lot of really nice city parks that I enjoyed as a kid, but they aren't quite as enjoyable in the winter. Although Mulick park had a killer sledding hill by 8 year old standards.
Instead of doing the high speed burn down 131, taking 37 south out of TC can be a nice drive.