[RNIB] very important features suggestion

Hello, dear developers of the MuseScore software!
I'm a totally blind composer and pianist. I would like to suggest some features that my friends (also visually impaired composers and musicians) and me need very much.
Please, make accessibility features equally available for all OS versions (windows, linux and mac os), because today we, blind musicians, can use only very old version of Sibelius (5.25) on windows with jaws screenreader only. As far as I know, there are no fully accessible music notation software for linux or mac os, so if you make your software fully accessible for all platforms, it really will be software №1!
Below are our suggestions:
1. Make a control, which allows to set key signature during the creation score wizard readable for screenreaders. You can use the sibelius 5.x style two comboboxes for selection sharps and flats and radiobutton for switching between major and minor, finale style slider, where going upwards increases sharps and downwards increases flats and radiobutton to choose major or minor, or any other solution - we just need to be able to control which key signature is selected now. Now this control is totally inaccessible, screenreaders tell us nothing.
2. Make it possible to switch between staves inside the score while editing using key commands, e.g. ctrl+alt+arrows up/down. Also we need information about what instrument is on this or that stave. For example, when we move to the stave 2, we need to hear information about what instrument we will edit while editing notes on this stave. Something like that - "stave 2, flute". Now software tells us only the stave number, not the instrument name. Also we need the focus to remain on the same measure - for example, we edited the second measure on stave 1, then switched to stave 2 and we should get in the second measure on that stave, not in the beginning of score.
3. Make the errors highlighting accessible - for example, if the note is out of instrument range, it is highlighted (red, I think), and we would like to hear something like "out of range" when the highlighted note is focused.
4. Maybe, the tabstopped toolbars is not very convinient thing, it would be much better if score will never lose focuse.
5. As for fast input it would be a very good idea to take the sibelius multipage numpad set - by pressing "+" on numpad user switches between some input types (common notes, more notes, accidentals, articulation, jazz articulation, tremolos and so on), by pressing numbers, ".", "/", "*", "-" and enter on numpad user chooses the input type - for example, in common notes mode 6 is whole note, 5 - halve note and so on, then by pressing letters he enters the note on the stave. If you choose this type, you can get sibelius shortcuts - they are convinient and all visually impaired users and many regular users know them well. In this case it would be very useful to tell us what kind of input is selected - when we press "6" in common notes mode we would like to hear "whole notes selected".
6. As for selected note speaking while navigating through the score, it would be a nice way to tell us something like that: "measure X (at the beginning of each measure), a4 ("a" - the name of the note, "4" - octave), quorter (for example). The octaves can be named from 0 (the lowest) and to 7 or even 8 - standard midi octave naming. It would be a good and useful to hear the page numbers, system numbers and all objects (not only notes) during score navigation too.
7. Also very important is to control what is going on with other objects, like tempo markings, key signatures, time signatures, clefs, slurs, articulations, dynamic markings and so on. When we switch to a new stave, we also should know, which clef, tempo and so on is actual for this measure on this stave, when we select a note if it has some markings or lyrics on it, we should hear them. And, certenly, we should be able to edit all these things.
8. Other information, which can be very useful for us. When we switch to the stave, it would be good to tell us not only the stave number and instrument name, but also, maybe, the instrument range - something like that: stave 2, flute, range from c4 to c7. Also when we switch to the new stave, it will be good to remind what measure are we in now - stave 1, flute, range is from c4 to c7, measure 5.
These are not all features, but only main features that require visually impaired composers and musicians. We understand, that it is a hard job to make notation fully accessible, but we need it really very-very much. In short words - we need all aspects of score, which can be seen by regular user, somehow reported to us using screenreader output. Sometimes we participate in competitions, sometimes make scores for orchestras or ensembles and always we need to produce high quolity score - we really can do it, but we need to know everything about notes and other objects, which we enter in score.
Thank you!
Best regards, Alexander.