May I offer a wish for the following:
It would be helpful if there´s a small border-line around the games display-area when we go into Slider Controls menu. Or change the colour of the "unused screen"-area into something other than black while changing settings in the Slider Control menu.
Also a Checkbox "Lock Horizontal Stretch to Vertical Stretch" would be useful: Enabling this should put the value from Vert Stretch into the Horiz Stretch. So changing Vertical Stretch setting will set the same on Horizontal Stretch and we easily get an 1:1 ratio between these two values.
Thank you for thinking over it.