Getting back to this....
I have mapped out more than I thought I had. The first map is Erie to Milford, NJ using the Pine Creek and Lehigh Gorge Trails:

https://ridewithgps.com/routes/6605807

This is the connector from Erie to Route Y at Union City that I came up with:

https://ridewithgps.com/routes/6743896

Unfortunately, I didn't note the camping locations, but they might not be too difficult to recreate. I know there is a campground in White Haven just before the start of the Lehigh Gorge Trail. I envisioned camping along Pine Creek one night (permit required). The second map currently ends at Dogwood Haven Campground. I have stayed there several times. It's dated, but quiet (nearly all mature seasonal campers) and totally shaded. The owner is a really nice guy who charges cyclists only $10. He doesn't even make me register. I just flip him some cash and all is good. You can make Philly from there. I can easily extend the map. I just didn't bother because I know the route like the back of my hand.

South of Easton I chose the roads on the NJ side, but you could stay on the D&L canal path right to the Dogwood Haven. I happen to like the NJ roads better. Carpentersville to Milford is very scenic with very light traffic. The trail can get monotonous, and the last time I rode it (last year) my bike and legs got covered with white dust from the crushed stone surface.