I can vouch for US 20 in Western NY. My grandparents lived right off of that highway on the east side of Ripley, NY. Ripley is the first town in NY coming in from PA. Stop at Meeder's Restaurant http://www.tripadvisor.com/ShowUserReviews-g48500-d2357178-r124676653-Meeder_s_Restaurant-Ripley_Chautauqua_County_New_York.html
and have a meal and some fantastic pie.
Lots to see and do in that area. If you are interested in wineries, there is the Chautauqua Wine Trail http://chautauqua-wine-trail.com/
. If you are there in the summer, you can find an abundance of fresh fruits and vegetables. Noble Winery http://www.noblewinery.com/
and Johnson Estate Winery http://johnsonwinery.com/index.html
are a couple of our favorites.
Westfield is next heading east. Another neat little town. Original home of Welch's.
Work your way up to Buffalo and see Niagara Falls!