There are a lot of good options near Rausch Gap, basically in PA sections 7 and 8. I haven’t yet done these as sections hikes but have day hiked extensively up there. One option you might want to look at is taking the Horse-Shoe Trail from the Gamelands parking area on PA443 on it’s last leg up to the top of Stoney Mt. and the Horse-Shoe’s junction with the AT. The last part goes up the valley of Rattling Run. If you head NOBO from there, it takes you past some of the best parts of section 7, especially The General, Yellow Springs village, and of course Rausch Gap itself. It’s a great hike for doing a short trip.
If you’re looking for a bit longer excursion, then you could do both sections 7 and 8 (the Susquehanna to Swatara Gap) and get much the same effect (though I do recommend the Horse-Shoe, which is a too neglected trail.) I don’t know the areas further south, though by all reports the Caledonia to Pine Grove run is lovely.
Hope this helps.
Good hiking!
Strategic