Here are the plans for a theoretical piano. It has all the workings of a regular concert grand, but instead of the keys facing the piano like normally, they face directly opposite of the body of the piano. ...
Directly opposite? As in 180 degrees? Don't you mean 90 degrees? Surely a "regular concert grand" would still be in its normal orientation, that is to say with the wavy side facing the audience, and the long straight side (on which the lid hinges are) away from the audience, so that the lid, when up, still reflects the sound towards the audience.
Obviously I realize that this type of piano would be quite costly and would not offer much to a performer other than the ability to face the audience while performing.
Quite so. Cost apart, one needs to ask what real benefit attaches to that ability. I can understand that a performer might wish to face the audience, but can also imagine that he or she might prefer not to (to avoid distraction, for one). Besides, unless playing from memory, the sheet music would be bang in the middle of the player's line of sight to the audience.
Tell us one thing about this auxiliary console you envisage, which faces away from the piano. You seem to be saying that wires run straight down from the keys to this tunnel. This seems to imply that this first set of wires will be protected by some sort of enclosure, i.e. the console is opaque and the audience will only be able to see that part of the performer which protrudes over the top of it, i.e. just head and part of the torso, possibly some of the arms as well. That being the case, Is there really enough benefit here over and above simply rotating a normal piano round? Then the performer can still see the audience by looking over the top of the piano. Admittedly, this does have the slight drawback that the lid would need to be removed, which would change the acoustics somewhat.
Of course your scheme is only helpful for solo piano recitals. For concertos or chamber music it is more important that the pianist be able to see the other performers than the audience.