I see no reason not to buy a touring bike. They have a slack geometry and a long wheelbase that contributes to stability and the gearing they generally have should work well with a light load and unloaded. Trails like the C&O really don't need a very wide tire. I'd be comfortable with the 32 mm tires on my primary touring bike.

On the other hand, the FUji may only need to be fitted to you better. It's also common to have neck pain early in the season or when you're in the saddle longer than usual. You may only need to schedule a few five hour rides with nothing else involved.

Brad