First, I would like to know enough about musescore to be able to implement these request myself, regardless of who actually implements such features; and I would like to know enough to be able to contribute sensibly to the project should it be me who implements it. I want to be better at programming apps like musescore, so it is a good place to learn.
What I would like to know, first and foremost, is the best way to approach plumbing in the features I am about to describe: this is not a request to the programmers of musescore to do it for me, it's just that 164,000 lines of code is more than I can comfortably read or keep in my head at one time. I like things small, and need them that way to work on them. Thus generally my questions will take the form 'how do I plumb this bit of code into musescore', once I have working code for what I wish to plumb in.
The way I would like musescore to work is to make mouse entirely optional, and keyboard (midi and qwerty) control as straightforward as possible. Vim and Renoise are good examples of how I like things. But the ability not to need to use the mouse pointer is very desirable for me.
I would ideally like the keyboard shortcuts to take the form of a stack of dictionaries (hashmaps) which take a keypress event (Something like 'Alt-X') and turn it into a command 'Turn NoteInput On'. The current shortcuts works a bit like this. But I would like a stack where the lookup goes through the stack top-down, stopping at the first match. Some of the commands would take the form 'Select ShortcutStack Foo' or 'Push ShortcutStack Bar' or 'Pop ShortcutStack'. Something like that. Related is the abilty to say 'Set GuiColour to Red' or to green or any other colour, so that the colour of the controls acts as a clear visual indicator as to what mode I'm in. This last feature is inspired by the way in vim I cannot see what mode it is in, or at least not without difficulty. In my head I can learn that if the controls are red, pressing 'Alt-X' does 'Say Hello' but if the controls are purple, 'Alt-X' does 'Load Template3'. This should be simple to program if I know where and how to connect it into the musescore code.