[salamanderjuice]

Android Options:
Boyue (now Meebook?) Likebook P78 - 7.8", SD card slot, 32GB, Android 8.1, 300PPI
Boyue Likebook P10W 10", no SD, 64GB, Android 8.1, Wacom Pen
Boox Note Air- 10", no SD, 32GB, Android 10, Wacom
Boox Note Air 2 - faster Note Air, Android 11, 64GB
Boox Nova Air - 7.8", no SD, 32GB storage, Android 11

Linux Options
Kobo Elispa 10", no SD, 32GB, random pen tech
Kobo Sage 8",no SD, 32GB, pen optional
Kobo Forma 8", no SD, 8GB or 32GB
Various Pocketbook models, some have SD card, some have ancient screen
Remarkable 2 10", 8GB no SD card, wacom,only really good for PDFs and Note taking

Honestly the Android devices are significantly faster than the Linux devices. Yeah Linux is more lightweight but you need that when your device has a quarter to an eighth the RAM and a fraction of the CPU power.I don't think obsolescence is really that big a problem, Chrome and Firefox run on Android 5, the latest Kindle app needs Android 6, etc. You don't need the cutting edge version to run the latest software. If you like reading manga off scanlation sites the tachiyomi app is excellent for that. I've had Kobos and Kindles as well as Boox devices and the Boox devices are the fastest, most flexible eReaders I've used.

I personally really like my Boox Nova 2 and Note Air.

There is a few color readers from Pocketbook and Boox but they really cut contrast so IMO not worth it.