Helpless with system spacing

[Stephan Schöll]

Hi folks

I would like to pull the systems vertically apart so that dynamics,
marks, lyrics a.s.o are optically (logically) grouped (law of
proximity). As you can see in the MVE the output is an optical mess.
After so many attempts and hours I give up. I read so many manual pages
(e.g. chapters 4.4.1 and 4.5 from the manual), followed and tried so
many mailing-list posts...

As far as I understand it's a VerticalAxisGroup thing. But adding things
like

\override VerticalAxisGroup.default-staff-staff-spacing.basic-distance = #30

  \override VerticalAxisGroup.default-staff-staff-spacing =
    #'((basic-distance . 10)
       (minimum-distance . 9)
       (padding . 1)
       (stretchability . 10))

or the same with VerticalAxisGropu.staff-staff-spacing...

either to Staff \with { \override ... } or to \layout { \context Staff
\override ... } doesn't move any of my systems at any time.

--- MVE ---
\version "2.19.83"

myNotes = \relative c' {
  c4\< c\> d\ff d \break
  e c\mark \default d2 \bar "|."
}

myLyrics = \lyricmode {
  some word to the me -- lo -- dy
}

\score {
  <<
  \new Staff {
    \new Voice = "melody" {
      \myNotes
    }
  }
  \new Lyrics \lyricsto "melody" {
    \myLyrics
  }
  >>
}
--- END MVE ---

Regards
Steff