The Ctrl + Alt + Greenscreen Custom Backdrops were specifically designed with photo studios in mind! These work similar to the Photographic Memory items by letting you add any photo or canvas/painting to them. Simply click on one of the green screens and choose a photo you want displayed on it! The aspect ratio/scaling will adjust based on the source photo.
This approach does have the disadvantage of being unable to scale using MOO. I did compensate for this by including three sizes that match the small, medium and large wall heights.