jordanss, did you do this ride already? You might be all sorted out already, but if not, here are a couple more random data points:

The "s" routes etc. that people are referring to are the state of PA official bike routes, which can be found here: http://www.dot.state.pa.us/BIKE/WEB/tour_routes.htm

I would trust these a gazillion times more than google bike routes, which are still a new technology and while appealing, are not very effective yet at finding good routes, just ones that allow bikes. Even that is not always the case.

www.crazyguyonabike.com has tourist journals, many of which have gear lists.

I would go for a wider tire for loaded touring than the 23 mentioned above, although you *can* ride a narrow tire on the crushed lime paths.