Hello. Everyone has it's own habits to use keyboard and mouse. And for keyboard shortcuts there is settings in (almost) every application, but as for mouse - it's impossible to change the way we interact with application.
I want to navigate thru document with mouse wheel (not the navigation bar, but in working area), it's so comfortable to drag page up and down, left and right by pressing middle button anywhere and drag it in other applications, it looks so natural to me. I don't like using left button for that, because I feel myself as on minefield, carefully place mouse in empty space (and when page is full of notes, texts, brackets, slurs and so on, it's not so easy to find empty space).
I understand, that some might like to do something else with the mouse, or leave it as it was, so, please, add ability to choose, what mouse buttons and wheel do (in editing and standard mode)