I'd suggest riding across PA along state route 6. It traverses E-W across the northern tier counties, arguably the most scenic area in that state. Not too populated either, and traffic can be a little easier to deal with. Be ready to climb and descend though.
In NY there is a route that traverses their southern tier following NY17. It is also an E-W ramble, but is more flat, and crosses a Native American reservation.
One could also tour the Allegheny National Forest, and mix pavement and surface roads in the "big woods". Similar riding to this can be had in the Adirondacks.