It would be great to have a feature where a placed graphic, text frame or object could be quickly resized using the contextual menus to a choice of standard aspect ratios (4:3, 16:9 etc..) there would need to be options to crop, resize content proportionally etc.. Add the ability to add your own user ratios and physical size dimensions like the Photoshop crop tool and it would be very powerful.

For example: it would be pretty slick if users could drop a 5:7 image onto their page and then right click to quickly crop to 16:9.