Thanks so much for sharing and for such a detailed answer! I understand where you are coming from, I don't have a tablet so for me an e-ink reader would not be too much (I work on my laptop most of the day and I don't like reading on the phone, so a device like that is a sweet spot for me).

I tend to mostly read bw manga (webtoons I read it on my laptop usually), but I heard the same about e-ink colored devices (and most generally that you "shouldn't" read bw on colored eink screen).

For the same reason as yours (mandatory calibre for transferring), I am looking at Onyx Boox e-ink devices, which are basically android tablets but with an eink screen. This gives me the freedom to install whatever app or sync I want, limit my exposure with something like nextdns, remove google stuff as much as I can, and things like that.

In the end I guess it's a balance between actual functionality and convenience, if a whole pipeline become too hard to manage than doing some parts manually might actually be better.