Depending on what route you take, the Railroader’s Memorial Museum, an Horseshoe Curve site in Altoona are pretty interesting as well. Sadly, there’s not a whole lot to see at the East Broad Top this time of year but forlorn buildings in the snow. (Gettysburg battlefield has the same problem)
There’s also the PA Military Museum in Boalsburg (near State College) The Daniel Boone homestead near Birdsboro,
There are also decent car museums in Philly, Turbotville, Hershey, Huntingdon, and Clearfield.
If you go through Clearfield, I highly recommend the food at Aunt Lou’s Cafe at the truck stop off I-80.
I also loved the Capitol Diner in Harrisburg. There’s this neat little Sandwich shop (Isaac’s?) just a quarter mile from the Strasburg RR that peddles a mean Reuben, too.