Thank you for your videos! Yes, the sound quality may be poor, but the playing is fantastic! You do like to rip up the piano.

And there is certainly time and room for that kind of playing. Regarding your reference to Ravel's
Gaspard, in my opinion it makes my point stronger, for Ravel wrote it for a standard piano and gives
optional notes if the Bosendorfer Imperial is available. I think your approach should be the same. Even those who play the Bartok
Sonata, will use
scordatura of the DD#/EEb (D#1/Eb1) to get one of the two required extra notes and then transpose by an octave the other, or simply use inversion or octave-transposition to bring the 2 required extra notes into the playable region. What a headache for pianists who want to play the work. Don't place such a burden on the performer, not to mention practicing it.
I listened again to the 6th movement, and find it a mixed-bag of language and quality. Consider that when other composers tell a story, they do so with a consistent voice that is all their own. You are using whatever you like at any moment, throwing in elements that
momentarily would be heard as, Debussy, Ravel, Liszt, Cowell, Crumb, Stravinsky and others that may be recognized by others. What kind of language is that? Do you want to tell a story with an atonal palet? Then do so throughout. Do you wish it to be impressionistic or post-romantic, that's OK but to change from moment to moment makes it sound..., well schizophrenic. This is the most difficult task for a young composer - discovering
their voice. If I had to judge what is the voice of Guida based on the 6th movement of your Sonata, I would have to say
pastiche. But that is more a
device than a
language. So you're still stuck trying to discover/invent
your language. The second most difficult duty of a young composer is to exercise discipline in his or her writing. The first of these is similarly staying in one language. I would personally like to hear the 1st movement of this work, to see if a
sonata-form can be appreciated. If not, then you have not written a sonata at all and should re-title the work as a suite. So often, young composers cannot do the simple mechanics of modulating from one key to another, or following a prescripted form. Have you tried a fugue yet? (not 18th-century style mind you; Have you played the Barber Sonata?). Too often the works of budding composers are nothing but free-forms or rhapsodies; this is an escape from discipline. You must learn your craft and by doing so
earn the right to compose in such undisciplined forms. This is what I mean by exercising
discipline. You have moments of real beauty in your writing, like at 5:20-30, but I get dizzy with the kalidoscopic changes that you take me through. Again, based upon the 6th movement of your sonata, I would add that your approach to composition is
pianistic, but to be great, it must transcend that, it must be purely
musical. To give an example of some of the worst pianistic writing that nonetheless soares as a musical achievment, consider the Beethoven Op. 57, iii. This aspect is a matter of maturity. In time you would advance from thinking in pianistic terms to more musical ones (that happen to be executed on a piano).
I hope this is more helpful for you.
Sincerely,
Eddy