Which reader do you have? I've been looking everywhere I can think of for a good 8-inch device, but I need it to run Android. Heck, I even tried looking into tablets with traditional screens and am having trouble turning up anything serviceable.
I have a 6" screen and it's too small. I got a 10.3" one and it was too large. But I'm starting to suspect those of us who primarily want to read are the only ones who want 8 inches, and we're a rare bread.
Viwoods AI Paper mini and Supernote Nomad if you want 8” Android. They’re primarily focused on the writing experience but they will run most Android apps and Koreader.
The downsides are that they are expensive and the Nomad does not have a front light.