I ride that area a lot. Which long hill got you dropped? Just curious.
Obviously, the roads along the river are mostly flat - some gentle rolling inclines, but, to either side are some truly wicked hills. The one that raises my lather the most is the hill leading out of New Hope on Route 232. I bet the first leg of that sucker is a mile long (and steep), then, when you get to what looks like the top, it the road takes off on another climb that's probably a mile and a half.
Glad you got in some good miles - and I certainly agree that the area is beautiful.