Arrrgh, maybe if I win the lottery one day I can create an e-ink coding and documentation setup. Would have to be Linux because newer Macs don't support more than 2 external displays unless you get the most powerful CPU.
LCD but persistent (if nothing changes very low power) and with colors (limited is ok, pebble time had 64) and higher frame-rates.
Contrast was suffering on those displays compared to the pebble 2 ones, but maybe there is something better now?