Okay here we go, first let me say something about the lay of the land water wise.
All downspouts around my home are connected in a system with a main discharge to the street.
My back yard is about 75 feet deep and open ground bordering forest. I sit on high ground and my lot slopes away from the property, EXCEPT in my back yard where the slope is about 2-3% toward the home. In general, however, water runs to the lots on either side of me.
The ground is HARD. Packed clay with chert intermixed. In summer it bakes rock hard. It is a little softer now with moisture, but is still difficult to dig in. Any rain 1" or more results in standing water in the yard. Hard rains results in obvious water movement across the ground, but not necessarily toward the house. Water percolation is SLOW into the ground and there is seepage into lower areas adjacent to my lot for several days after a hard rain or wet spell, but again my lot is higher than surrounding lots. I picked this on purpose.
Now for some data:
My crawlspace is about 2500 sq feet give or take 100 feet. It is not a rectangle, it has various 90 degree lines depending on the footprint of the rooms above.
There are 14 piers in total. Each pier is 15.5 inches square and composed of stacked preformed concrete blocks.
The area around the piers are dug out packed chert/clay presumably where they poured concrete footings. The dirt was
not replaced. Two of them collect water; the outer foundation on the backside of the home is almost always dark with moisture unless prolonged drought.
The joists run parallel to the problem area, not perpendicular. I liken it to a folded crease on a piece of paper.
The crease (and wall above) is about 9 feet in total, but pronounced directly under the 6 foot china hutch.
There is NOT a pier directly under the sag. Closest one is about 2 feet away to the side and not centered on crease.
This also happens to be the pier that collects the most water sadly.
The slope of the crease is about 3/4 inch per 4 foot on the dining room side of the wall both in the living area and in the crawl.
The slope of the crease is about 1/2 inch per 4 foot on the kitchen side of the wall both in the living area and in the crawl.
Attached is a picture of the crack in the wall that is on the crease, dining room side. There are no cracks on the kitchen side.
The doors and windows that are out of square upstairs are not so much as to be seen in a picture so nothing there. I can take more pics if you need something specific. I just noticed my hardwood floor directly below this crack is also cracked. The flooring runs perpendicular to the crease and the floor crack is about 1/16 inch in the grain.