We're in PA too, and drove to Florida and back the past 2 summers.
Two years ago we stopped overnight in SC. On the way home, we took a short 3-night trip extension in Myrtle Beach, SC. It's a bit of a drive off 95, but there was plenty to do. Of course, we were there in June, so the beach was our main entertainment. But there are tons of things to do there year round. There are shows, aquariums, museums, and shopping there.
Last year we stayed outside of Savannah on the way down (on the north side of Savannah - before entering the city). We only stayed the night and then continues driving.
On the way home, we stayed in Pigeon Forge, TN. it's not off 95. Rather it's off 81 (we had been staying in Tampa, so we were to the west to begin with).
I totally preferred the drive home on 81. It was much more scenic. Not quite as many rest stops, but still enough to fill the rest stop needs. But it was so much nicer than 95! Lots to do in Pigeon Forge too. I would go back there again in a heartbeat!
We try to push through as quickly as possible on the way down, but we need to break up the ride home. I am sure you can find a great place to stop.
But if I were you, I would try to get further than Savannah on the way home before stopping. You still have quite a drive from Savannah to home. We felt the same way with Myrtle Beach.
It was just under 10 hours from TN to the Lehigh Valley.
have a great trip!