So I bought this stand from Amazon and it works very well. It does hold the 12.9 iPad Pro (2019) without drifting or slumping. It’s not too heavy overall, so not a chore to carry it from living room to patio to bedroom.
Added to my wishlist. Thanks!
Update on my purchase, above — I don’t use the handle anymore. OTOH, I’ve grown more comfortable with holding the big iPad in my hands.
What I really want is a paper-thin iPad that folds down to pocket size as an iPhone, then folds out to a 13" iPad with keyboard. Maybe in 2022?