What would be cool is not having one screen but TWO. One that controls the on-board sounds part, it could be the smaller screen and the bigger one (on the side where the registers area would be) of the accordion. The larger one (arranger portion), could be a 5" X 7" size and swing out with a well laid out control touch surface.
Something like this would be finished off with wireless
bi-directional analog transceiver with a 250' range and a
bi-directional wireless MIDI, where if attached to a laptop would be able to send/receive sampled sounds from a laptop and come out either it's built-in speakers or out the analog transmitter to an external amp or sound recording device. Support for a 10-20 button BT pedal for arranger and accordion sound setup.
You'd be looking at a $12,000-$15,000 unit, possibly more if you had the functionality of something like a Ketron EVENT X integrated in it.
I wonder how many they would possibly sell... at that level, not many, I'd bet, as it is even MORE of a niche instrument.
One thing I hate... again, we see it in the video above... we have 1 hand for melody, one for the bass and to pull. An accordionist with this setup is forced to take away the PLAYING hand to make changes, introducing pauses/delays... ugh, how I hate that!
Foot pedals, dudes... foot pedals!