Show the instrument range as a colour - example flute. Flute has three registers, the lower middle and upper, then it has partials or extra notes that can be made.
If the piano keyboard in the Key Editor, or even the lanes themselves, took on colour shades to indicate which part of the range you were in, this would help. Also the note colours could change - especially when out of range. This could be for all the main western instruments (selectable). User definable colour maps should you have an allophone, or an octopussette in your hands
Make it possible to get a selection of notes to full screen (and back) both vertical and horizontal, with one click. This would be a real help.
Big one: Make it possible to click on a note and find out its properties in terms of Library, Articulation, CC values, sound. Make it possible to see how the track is layered in the KeyEditor. Make it possible to change these values and create cross fades.
Make it possible to see as single or piano notation in a ‘controller’ lane.