Details needed for ancent music scores

Hi,

All of this is very specialist, I know, but these details are required / useful / convenient when editing score for older music. They are listed in very approximate order of importance.

1. Option to have bar line only between the staved, rather than across them.
2. Option to have note values to 'cross' the measure boundaries, without breaking them in two tied notes (see example).
3. More mensuration signs: in addition to C and cut C, also 'dotted' C, O, 'dotted' O and cut O are needed. I can add the needed glyphs to the MScore font, but adding them to the programme internals is above my head.
4. Option to create time signatures without denominator, like "2" or "3" (positioned in the middle of the staff); an implicit denominator can be assumed (usually is "2", but it is better to make it selectable).
5. Option to add mensuration signs to (real) time signatures, to create 'time signatures' like "C 6/4" (equivalent to "6/4" as far as the programme is concerned).
6. Option to have breves and longae with heads made of 4 segments rather than of a circle with two lines at the sides (see example).
7. Option to use mensuration signs as real mensuration signs. This may be difficult as it involves changing the values of notes (under 'dotted' signs, the brevis (whole) spans 3 minimae (halves) rather than 2), but would be a GREAT bonus!

Thanks!!

M.