Hello ! Long time reader, first time poster.
On my Kindle, going the "Series - Number - Title" way is often awkward when the full title ends up larger than the screen,
however the author's name (in a smaller font) takes up very little space.
I've crafted (with the help of another post in this very forum, sadly I don't remember whose...) a very ugly plugboard for the
authors field that seems to work for most author/series numbering combinations :
{author_sort:list_item(0,\,)}{authors:re(^[^&]*,)| |}{series:| - | - }{series_index:'contains($,'\.',format_number($,'0 5.2f'),format_number($,'02d'))'||},{author_sort:re (^[^\,]+\, ([^&]+).*,\1)}
(told you it was ugly)
It leaves the title alone but changes the author into (brackets meaning only if applicable) :
"First author's last name[ other authors][ - Series name[ - Number]], First author's given names"
Examples:
Donaldson - Thomas Covenant - 07,Stephen R.
Taylor - St Mary's - 08.50,Jodi
Pratchett & Neil Gaiman,Terry
This completely mangles the on-device metadata BUT it appears correctly on the list (First name Last name - Series - Number) and it sorts by author's last name first, then by series, then by number.
I'm sure the plugboard could be improved, but the principle seems sound to me -- and it is the only way I've found that allows proper sorting by title OR by author on a Kindle.