Good advice! I would also add something specific (that is not relevant for anyone but for people like me). Face ID is really difficult for me to make it work on 11 inch tablet let alone on 12.9 inch. I do not have the strength in my hands to hold the device the way it has to be for Face ID to work. So if people have concerns about this they should consider the screen size as a factor.
Interestingly I find FaceID to be more reliable on my iPad 11“ if both are laying flat on a table for sure, though that‘s a tricky angle; upright or in the keyboard or in my hands, it’s generally a wash.
I too am struggling again after feeling committed to the 12.9”. For handwritten notes and PDF reading, the bigger screen is great except that I need to lay it down to comfortably do those activities; for eBook reading, the smaller form factor is clearly a win (showing about double the amount of text of my iPhone 11 Pro Max which is still a big advantage). Video viewing doesn’t matter to me since I wouldn’t hold the device up for that activity but would totally dock it in the keyboard.
As for the magic keyboard, yes the 12.9 is definitely more comfortable for extended periods of time, but the 11” one is generally perfectly good and still a huge upgrade from the keyboard portfolio I used extensively since 2018. I’m not sure the disadvantage of the ergonomics of the smaller keyboard outweigh the disadvantage of the larger iPad as a tablet?
Battery wise I’m totally satisfied with both, not sure that would make or break my decision. Either way, I‘m finding I’d be totally thrilled with what effectively is a super compact 2-3lb laptop replacement which can quickly become a 1-1.5lb tablet for consumption (or for PDF annotating or handwritten notes).
I don’t have a personal Mac at home anymore (and can maybe count on one hand the number of times I booted up my 16” MBP before I sold it) but we do have a docked MBP for the household that can always serve in a pinch; I’m wondering if that plus my 11”+MK is the way to go.