Make annotating student submissions more user-friendly

It would be nice to be able to expand the window for viewing and annotating student  papers. One way to do this would be to make the right-hand column for grades and comments adjustable, so that the professor could expand the viewing window. (I realize that one can use "Presentation Mode" or open the document in a new window, but if you do either of those things, you are no longer able to annotate the document.) The current default dimensions of the viewing window require the font to be very small and hard to read if the full width of the submitted text is to be visible. Thanks for considering!