Is Pennsylvania more similar to New York or Ohio?

[If my soul was made of stone]

Western Pennsylvania is very clearly aligned with the neigboring parts of Ohio, both along Lake Erie and in the Mahoning/Shenango Valley. The parts of NEPA considered part of the NYC metro are much more distant and their cultural connections to the urban core much more tenuous. Philadelphia does not dominate Pennsylvania in the same way that NYC does, although much of interior PA has some aspects in common with upstate. Both Pennsylvania and Ohio also have a substantial Amish influence in certain regions that New York lacks.

[If my soul was made of stone]

Central PA and Upstate NY are quite different politically. You have to get pretty creative to draw even a single Dem-leaning Congressional district in Central PA, but there are several in Upstate NY.

Would a Harrisburg-Reading district work? Maybe with State College added in?

It's possible to draw a fairly blue Harrisburg-York-Lancaster district, but it would be quite ugly. State College-Harrisburg-Reading sounds like a bit of a stretch.

[If my soul was made of stone]

As whole OH and not even close. Might be more like Upstate NY though.

Yes, going by PVI, the answer is Ohio.

Pennsylvania has voted to the left of New York three times since the Civil War: 1952, 1956, and 1984. The base of the Democratic Party in western Pennsylvania at the time resembled Ohio's coalitions much more than New York's, although they've since converged somewhat.