it would be great if something cheap from aliexpress could be adapted somehow :o)
OLED QY with low power draw.
main problem of course is the batteries don't last anyway (so it needs a powerbank).
( ? would yamaha ever do a modern QY ? ....
imagine the whole thing on a compact aira size pcb with a usb-chargeable (replaceable) battery, just charge it up via usb, transfer all your stuff via usb .. )
(and cheaper to produce now if they just repackage the same sort of thing, with bigger audience, and (enhanced operation and features) )