Different bar lines, musica ficta & lyrics font style

[Marcel Korpel]

Dear all,

When using Lilypond to typeset a transcription of a Palestrina Mass
the past couple of days, I stumbled upon several things which bother
me more or less:

1. Is it possible to change the bar line depending on whether the note
values exceed the measure or not? For instance, when typing

dl = \set Timing.defaultBarType = "dashed"
nl = \set Timing.defaultBarType = "|"
\new Voice \relative c'' {
   \clef G
   \time 3/1
   \set Staff.timeSignatureFraction = #'(3 . 2) % tempus perfectum
   d1 d2 c1 c2  d1 a2 c1 \dl b \nl a4 g a1 g4 a b c
[etc.]
   }

it would be nice to automatically change the bar line to dashed when
the b exceeds the measure, instead of enclosing it with macros that
change the default bar type to dashed and back.

2. When notating musica ficta using 'suggestAccidentals', an
accidental should be written above the bar for every altered note. At
the end of a section I wrote

\new Voice \relative c'' {
   \set suggestAccidentals = ##t
   \clef G
   \time 3/1
   \set Staff.timeSignatureFraction = #'(3 . 2)
   [...] f2 g1 fis4 e fis1
   \set Staff.measureLength = #(ly:make-moment 4 1) g\longa
   \bar "|."
 }

and only above the first f an accidental is printed. I know I can
place it manually adding '^\markup{\sharp}', but I don't think that's
a good solution.

3. When entering lyrics I need to italicize part of the text (to
indicate the text is my addition). But I get error messages when using

text = \lyricmode { Ky -- ri -- e e -- le -- i -- son
 \italic Ky -- ri -- _ e e -- _ _ _ _ _ _ _ le -- i -- son
 Ky -- ri -- e e -- le -- _ _ _ _ _ _ _ i -- son }

or several variations on \italic.

I ploughed through the manual, but I couldn't find a way to deal with
these things.

Your suggestions would be much appreciated!

Kind regards,
Marcel