Good info, sort of reinforces my decision - I was knocking around an 11" vs. a 12.9", both latest gen pro models with the same CPU/GPU, small bezels, Pencil 2 support, FID, etc., so really just a difference in physical/display size. From my perspective, the 11" isn't that much more portable vs. a 12.9, neither fit in a pocket, either fit in a small bag/backpack pouch, and while there's a good $200 or so difference, I wanted the most/best usability.
Maybe on a sofa, with a little less, weight, the 11" is a little more "hand friendly", but what it came down to was screen real estate. The 12.9 has a wider ratio, so seems to be terrific for using in portrait mode, and then if it's in landscape - especially if docked with a KB - it has more height in landscape mode (in terms of ratio), the 11" is a little taller/wider, so probably a touch better for movies in ~1.7 widescreen.
Since this was probably a primary mobile device for me, I wanted it to be as much of a "laptop replacement" as possible, so figured for that, bigger is better. The funny thing is a 3rd Gen 12.9 model is only 11x8.5", it's the same as a [letter] sheet of paper! That works for me!
I actually needed something to show some prototype work, and almost just scored something like a 10.5 Pro, which is still an excellent tablet, but I also wanted to experiment with this as a primary mobile device, possibly the wife using it with a KB, mouse, display in the near future vs. a notebook, I want to setup the little artist in the family with a Pencil 2 and Procreate.
And comics, so many comics I want to read, hahahaha