Thanks for the suggestions! 
We will consolidate the suggestions and propose a spec and pattern.
Basically, we don’t want to overlay it with a graphic ???*?? pixel graphic LC but a segment LCD like in the picture. It could be very big number with customized font and lit just like 7 segment LEDs.
Of cause controllable with serial, maybe el electronic brick 4 pin connector for easy control and setup. RGB LED is not an option but must have.
We have been knocking doors of e-ink suppliers but still not able to get a reasonable cost/MPQ to start with. Can’t wait to have on myself though…