A touch screen implementation on any BK gear wouldn't be efficient unless the display screen size was increased 4 to 5x bigger then it is now first off. Or having an "optional" iPad connected be able to do touch screen duties....anyway as it stands now on the BK series it is what it is,....that ain't gonna change. YOU just have to be happy with the way it is or wait for the next wave of Roland series arranger KB's down the road.
Personally I can work with either method efficiently on stage.
For me I'd rather have "MORE BUTTONS & KNOBS" for All menu solutions.