This is really cool, thanks for sharing the journey so far.

One potential idea - it might be worth looking at overseas manufacturers to see if they can offer a similar display at a better price point. I did a bit of digging on Alibaba, for example, and found a 25" E-ink display with the same resolution as the Boox for around $1000 (and the price goes down to $500 if you order 100 units or more): https://www.alibaba.com/product-detail/25-3-inch-e-paper-dis...

Seems like they offer a color E-ink display option as well, which could be worth exploring.

Note: I don't have any affiliation with the above company, it was literally just the first one I found when searching. I'm sure there are many other options available as well.

Have you seen any that include a touchscreen? Would be nice for extremely simple home controls (e.g. thermostat, music).