Some of us really only want a piano that you can play on stage. Needs great sound, but mostly piano sound.
The weakness of virtually every digital keyboard out there is the pedals.
Why not put a mini computer/audio module into a box with top-quality pedals on the side. Make it look nice. Make it heavy enough to not slide around. Make the computer controllable from an iphone/ipad/ipod. It would take USB or MIDI from the keyboard and do the rest, with balanced 1/4" stereo output.
Maybe the same idea with a couple of swell pedals for organists/synthesists. But put it all in one box with a handle.