Okay, so I’ll preface this by saying I am absolutely fascinated by e-ink technology, and I believe there is a lane for it. I am typing this on a Bigme Hibreak, a smartphone with an E-ink screen, and I have owned two Boox devices thus far. If you manage your expectations and you have the patience to tinker and dial it in, some of these devices can be perfect. The Boox Palma looks like a very practical device, although I haven’t used it myself. It seems to be very lightweight, and I can say from experience that the Boox software is pretty user-friendly (although not necessarily beginner-friendly; some settings tweaks are needed to optimize the experience). The Boox software is generally pretty stable, and the generic reader app is one of the best I’ve ever used. As another user pointed out, their software is not open source, so you may want to take that into account, but I haven’t encountered an E-reader company that does publish open source software (or hardware, for that matter). For what it’s worth, I had a Boox Nova Pro and replaced it with a Boox Nova Air C, and I have very few complaints. Just don’t order through GoodEreader. They are a bunch of assholes.
Look at the Bigme Hibreak. It might be up your alley.