RhythmicStaff - gray-scaling and getting rid of double heads for chords

[andersvi]

Id like to make a smaller RhythmicStaff with some special qualities,
like smaller font etc.  This one works fine, but i have a couple of
things id like to fix[1] (see below):

rytmestaff = #(define-music-function (parser location navn rytmer) (string? 
ly:music?)
               #{
               \context RhythmicStaff = $navn {
               \set Staff.fontSize = #-3
               \override Staff.StaffSymbol #'color = #(x11-color 'gray60)
               \override Staff.StaffSymbol #'staff-space = #(magstep -3)
               $rytmer
             } 
               #})

1) Id like to gray-scale the whole staff.  Is there a simple way[2] instead
of overriding zillions of objects w. properties to draw everything
inside the RhythmicStaff context in 'gray80?  Ie:
  
       \override Staff.StaffSymbol   #'color = #(x11-color 'grey60)
       \override Staff.TimeSignature #'color = #(x11-color 'grey60)
       \override Staff.Clef          #'color = #(x11-color 'grey60)
       \override Staff.NoteHead      #'color = #(x11-color 'grey60)
       \override Staff.Stem          #'color = #(x11-color 'grey60)
       \override Staff.BarLine       #'color = #(x11-color 'grey60)
       \override Staff.Beam          #'color = #(x11-color 'grey60)
               

2) For every chord in the input i get a 'doubled' note-head in the
RhythmicStaff?  How to get rid of those?  Is there a chord-engraver or
notecolumn-engraver i can grab and do something with inside this
context?


Footnotes:
[1] I am honestly doing some research before asking here.  Before asking
here im looking in the manuals ive got, searching the .info pages, and
finally the web. 

[2]  Guess what, im starting to beleive there is...

Thanks,

-anders