Been to Traverse City and area several times, in the 50's and 60's, and again twice in the 21st century now that it has become a favorite resort area for the downstate wealthy middle class. In the summer there's always something going on, something to do, with regular performances out at Interlochen, sailing on the bay, the large inland lakes, and on out to Lake Michigan (though Frankfurt and Petosky have better Great Lakes access).
If camping or RVing, we preferred to use the campgrounds at Interlochen state park, could walk over to the Arts and Music camp. Downtown TC is more about shopping and being seen, for that we found it more convenient to stay in a hotel. There is a SP at the south end of the bay, some campsites on the lakeside, others across the highway, both usually tightly packed with RVs too big for the sites on summer weekends. A few commercial RV parks in the region better manage space, but Interlochen is my favorite because it has more of a park atmosphere without as much crowding.