This is an ambitious road trip.
My take on a trip like this:
Day 1: Drive towards NYC, pick a place to sleep north of NYC
Day 2: Quassy & Lake Compounce, try SF New England in the evening
Day 3: SF New England, drive towards SF Great Adventure. (You will get stuck in traffic around NYC!)
Day 4: SF Great Adventure
Day 5: Dorney Park & Knoebels(not wise, but if you run trough Dorney possible)
Day 6: Hershey Park, drive towards Pittsburg
Day 7: Kennywood, drive to Sandusky
Day 8: Cedar Point
Day 9: Drive home
This way you won;t have a long drive home, when you are already tired. And still get some kickass coasters along the way! Save I-305 for another trip, where you could visit Busch an Carowinds too.