Rivnuts from Homestead, PA on 9/25/2021 10:18:53 PM:
In my opinion the towns themselves are not the highlights of the trip. I guess that's a backhanded way of saying the towns themselves are not particularly special such that I wouldn't plan my trip to visit a particular town in and of itself That said, you may have a particular interest in something such as, say, the civil war, which would lead you to perhaps want to stay in Harpers Ferry.
Of course the two terminus towns of Pittsburgh and Washington have a little something for everyone so you may want to stay an extra day or more in these cities. The choice of cities in between is typically a function of your itinerary including distance desired to ride each day and/or the length of time you have allocated to complete the trip. That will dictate what cities/towns you stay at. Once those are known you can evaluate the lodging options and points of interest in those cities.
With a little more information about your preferences, interests and itinerary those on this forum will have a variety of recommendations on where to stay and what to see in those cities/towns.