I agree that this is the simplest way; algorithmically, but ultimately also for humans.
and do whatever with the few which don’t fit
That’s where the dozen different standards come from.
My first impression is that Bulgarian language uses fewer characters than Russian and Ukrainian. Not fewer sounds, though, it just doesn’t have characters like “ё” or “ї”, which represent pairs of other existing characters anyway. (Though you still have “ю” and “я”, which work the same way.)
I agree that this is the simplest way; algorithmically, but ultimately also for humans.
That’s where the dozen different standards come from.
My first impression is that Bulgarian language uses fewer characters than Russian and Ukrainian. Not fewer sounds, though, it just doesn’t have characters like “ё” or “ї”, which represent pairs of other existing characters anyway. (Though you still have “ю” and “я”, which work the same way.)