It looks like a cool project. I wonder if anyone is working on higher PWM frequency for people who are PWM sensitive. Most ereaders with front lights use PWM at a fairly low frequency to control brightness and it can be very taxing on the eyes. Dimming using DC regulation is slightly more expensive but it should be fairly manageable with this kind of open hardware project.

Good display has a round 1.65" color eink that includes:

Red, Bule, Green, Yellow, Black and White

Hopefully their product QA/QC is better than the marketing side.

The prices are low, with the 7.5" touch display with front light under $50, 10.3" under $150, and the 13.3" under $360. I say "under" because they show a sale price, but the price I note is the full according to the page.

$60 for the rest of the hardware according to free-ink makes these all good options pricewise, plus the cost of a proper case. I'd probably do one out of wood personally, I feel like that would be both fun and look really good.

Overall a cool project, I'm going to have to check it out some more later.