Not sure if it can be done but, i think it would be great if the game´s window mode could be maximized so that the windows borders fully vanish at the borders of the screen, means the only way to move the mouse out of the window would be the taskbar if its forced visible.
First would this max the use of the screen for the game without loosing the ability to start other applications (via taskbar) and second would it reduce the risk to click on the desktop in the heat of battle. Not sure if that happens to others either, but if monsters walk around me repeatly and i have to turn my char to follow, moving the mouse around, it sometimes happens that the pointer crosses the window´s borders so that a click would make the the game window inactive.