Mind that visual reading – I actually do not know about tactile, but I'd guess it may be similar – isn't about letter by letter, but about the impression of entire words. Here, similarity helps a lot. (Otherwise, you have not only learn the new alphabet, but the gestalt of all the words anew.)

Regarding Braille, my grandmother became mostly blind at old age. Having maintained an interest in books, while finding herself increasingly restricted with regard to her radius of action, she tried to learn Braille, but eventually gave up. At her age, she couldn't feel the differences anymore. Tactile resolution and significance do matter. (I'd imagine, in her case a similarity to what she had been used to may have also helped.)

Generally – while not knowing much about the viability of the specific implementation –, I think, Fakoo is a great idea.