[dredmorbius]

The BOOX devices do come with an OTG port, and it's possible to attach a MicroSD card via that, though the arrangement is somewhat perilous (risking physical damage to the card, OTG attachment, and port) and not ideal.

I too would have preferred an integrated MicroSD slot. Current cards are available in 1TB+ sizes, which should satisfy even my prodigious appetite.

I do make use of handwritten notes as well, both in documents (Neoreader) and in the notetaking app. I've found that far more useful than I'd anticipated, though searching notes is of course challenging.