An actual moving average of 10 mph is pretty slow. Fully loaded over rolling terrain I average probably around 13 mph depending on conditions. One thing you have to keep in mind is thatit's not always possible to simply stop at X number of miles each day. Places to stay may be located in such a way that you need have to do 40 miles or 80 miles or something in between.
You don't want to avoid 209 when possible. In fact, some of 209 is combined with I-80 so you cannot ride on it. You need to take Bus. 209, such as through Stroaudsburg and E. Stroudsburg. That can be a royal mess. Traffic can get lighter the furthern north you go until Milford, PA, but 209 is not as scenic as the NJ side.
I think you are referring to the Paulinskill Valley Trail out of Columbia, NJ. I believe that was damaged in places by one of the storms NJ has experienced during the last several years. Also, that trail is south of the ridge that you need to cross to get to the river. That can involve some steep climbing.
When I get a chance I will post links to some maps for you. I can give you maps for what I did from Cumberland to near Philly. I can also show you a map from the SRT to L'Ville, NJ and then up the river to Port Jervis.