Well, Steve did say "irrespective of cost", which makes it all a bit pie-in-the-sky, really. If all the things that people have been asking for were brought to be, just how many would actually shell out the kind of cash that these dreams would cost? Not just the afficionados here, but in the world at large. I'm guessing it wouldn't be that many, most probably not enough for Yamaha to produce these things on the grand scale of the Tyros's and PSR's of this world.
Of course, the realistic goal here is that SOME items on this collective wishlist may well appear. Trouble with that is, only a limited number of folks will be happy and the 'shoulda done this, shoulda done that' saga will continue into forever. It's the old 'you can please some of the people some of the time, but not all of the people all of the time'.
Kudos to Steve Deming for asking, though.