After reading this thread, I'm amazed that no one has mentioned the work being done on alternative keyboards (and on alternative music notation).
The main point is that the design of the piano has held beginners back for centuries, and likewise has hindered the development of music notation.
Unfortunately the design of the piano keyboard requires that fingering change when you change key. The guitar doesn't do this, neither does the button accordion.
Whatever, a number of keyboards have been developed where the fingering does not change as you change key.
That is an absolutely horrible idea. It might seem intuitive at first ("Just alternate keys!") but its impracticality becomes immediately apparent and is directly acknowledged in the site you linked:
>> There’s just one drawback: the monotony of such an arrangement. How can we find our way on such a keyboard? Recently, the French musicologist Laurent Fichet remarked: “This system would certainly be much more rational than the keyboard of today, but one may wonder how players would locate the different notes with such a systematic and uniform layout.”
The French version of the article then goes on to suggest many variations of ways to avoid being lost on a keyboard without any obvious pattern (the English version only lists one, briefly). Some include coloured keys.
It is beyond obvious that the simple, intuitive solution proposed at the start produces a cavalcade of complications none of which has a simple solution.
Not to mention: despite what the linked site suggests, learning how to position your fingers on the keyboard is the least of your problems when you learn the piano, just as learning to touch-type is the least of your problems when you learn how to code.
The symmetric keyboard is a fun concept, but its existence as niche is similar to why QWERTY is still dominant. Inertia. Most keyboards have it, and computer keyboards are much easier to change than pianos. Once you have reached a certain fluency, the jump needed from this local optimum to a new one is prohibitively high/far. For musical instruments, this would mean you would be unable to play anywhere but at home.
That's a huge drawback and it's really underappreciated by everybody advocating for the "better" concept.
Besides, there is the unrelated drawback that especially for a beginner, it's really easy to learn simple tunes with just the white keys on a piano. Throw in a black one now and then and you can get quite far and have fun as a kid. This would be much more intimidating with a symmetrical layout.
The last link is very interesting, but it doesn't look like a sheet music alternative, since it only gives you the chord progressions and not the constituent notes.
Also, good luck printing it on paper without the animations :)
The main point is that the design of the piano has held beginners back for centuries, and likewise has hindered the development of music notation.
Unfortunately the design of the piano keyboard requires that fingering change when you change key. The guitar doesn't do this, neither does the button accordion.
Whatever, a number of keyboards have been developed where the fingering does not change as you change key.
Start here https://www.le-nouveau-clavier.fr/english/
and https://musicnotation.org/wiki/instruments/isomorphic-instru...
Particularly the https://musicnotation.org/wiki/instruments/wicki-hayden-note...
But please start searching and reading on the following topics:
Isomorphic Instruments, the Xenharmonic Keyboard, the Janko Keyboard, Linnstrument, Lumatone, Dodeka, Chromatone, Balanced keyboard.
And for just a glimpse of an alternative music presentation:
https://www.youtube.com/watch?v=NQ7LkWCzKxI