Extent of hairpins

[David Sumbler]

I find that consecutive hairpins (e.g. {c\< d\>}) are too closely spaced
in standard Lilypond output.

Looking at Elaine Gould's wonderful book "Behind Bars", I notice that in
such cases her examples show one hairpin ending at the left-hand edge of
a note and the next beginning at the right-hand edge of the same note,
although she does not appear to say this - or if she does, it is a rare
example of ambiguity in the text.  (She says "good practice is to start
the hairpin on the left-hand edge of the note and to finish in on the
right-hand edge of a note"; looking at her examples, by "the right-hand
edge of a note" in this context she means the left-hand edge of the
following note, which is arguably the end of the duration of the first
note.)

This spacing gives a separation between consecutive hairpins of one
notehead width, centred on the note, which looks just about right to me.
Lilypond's default separation seems to be half of a notehead's width or
slightly less, centred on the note.  How can I alter this to increase
the separation to a full notehead's width?

When hairpins are not consecutive, but stand alone (without starting or
terminating dynamics), Lilypond appears to start a hairpin at the left
edge of the first note and end it at the right-hand edge of the last.
This has always looked wrong to me, and judging from p. 104 of her book,
it does to Elaine Gould too.  How can I change the default so that
hairpins normally stop at the left-hand edge of the final note?

David