While in drawing view, using the scroll wheel scrolls the current slide. 
However, I find that a far more useful behavior of the mouse scroll wheel in 
drawing view of Impress is the one in Powerpoint - scroll through slides in the 
presentation. Usually you want to see how the presentation flows while creating 
it and scrolling through slides is a very convenient way of doing it. I know 
that I can use the page up and down keys to scroll through slides but the mouse 
scroll wheel should also be available for that.


How about something like this: currently shift + scroll is unused. We could use 
shift + scroll to scroll around the current slide in drawing view and use the 
scroll wheel alone to scroll through the slides in forward or reverse order 
depending on whether the mouse is being rolled up or down.