Great article, thanks for that!
I organise mostly by genre but not entirely. Within a genre, I have a 'what fits best where' approach, where authors of whom I have more books take priority over authors of whom I only have one or a couple of books (this is because I want one author's books to preferably all go on the same shelf next to each other). I put my favourites more in the shelves in the middle and on eye-height, top and bottom shelves are on occasion reserved for books I don't often plan to (re)-read or that I've not got as much interest in or that I don't like as much, or that I don't mind as much getting dusty in the case of it being the bottom shelf. Within biographyes & memoirs and for information books, I have them organised based on subject or series, so all autism memoirs are on the same shelf (and are actually together with information books about autism!), same with all AD(H)D related ones. Memoirs by people who are famous for something (ie. from TV or music), are on one shelf. All memoirs about mental health, physical health, and stuff like that, without the people being famous / celebrities etc, are near each other. All my Horrible Histories books are on one shelf, etc.
Anyway, I have to leave now because I have an appointment! Can't type more sorry..