I like the technical fun of it, but no musician is ever going to give a crap about this. We have hundreds of years of the evolution of music notation and it is pretty comprehensive. Just because there are only 12 unique notes in western music doesn't mean base-12 to notate it makes sense....that completely strips out context of what you are playing.
For example...in the key of aminor when you make the five chord major to create a resolution back to i (aminor) you raise the 7th scale degree. That means the G becomes G#...Ab is the same pitch but writing it that way is wrong. An EMajor chord is spelled E G# B, not E Ab B. Now if you spell that as 9 0 4 you have stripped all context out of the music. Musicians aren't just player pianos, they analyze the harmonic structure of the music the inform phrasing, shape, tone, volume, and pacing (acelarando, decelerando, ritardando, etc).
Whenever I see something like this trying to reinvent standard notation I feel like it is usually from somebody who can kind of play an instrument but can't read music or can't read it well because they haven't put the years of work it takes to be a proficient sight reader and they haven't studied harmony/music-theory.
One of the most important things about musical standard notation is that it is - standard - you can hand it to any musician on any instrument and they can make sense of it quickly. It is a skill that takes a lot of practice but it is what allows musicians who have never met each other to be hired for a gig and show up and play together without ever rehearsing.
This approach won't teach you to "see" music either. It forces pure mechanical number memory....you won't see harmony and be able to quickly notice that - for example - a line is just moving the chord up in inversions and since you know harmony and your chords you can sight read that part without ever even reading every individual note.
But still a cool idea from a hobby perspective.