You explained why you think this work. Less about the the what is stopping changing it.
Why would having the option to change the library structure pose a problem ? Those who like it that way would let that way. Or would it just be too much work because calibre is too linked to it and it would requires re-doing almost everything ?
And see my point, I'm trying to speak calmly, but every time someone speaks about this it ends up by
. Kind of stupid.