... When I set up my doll cases, I bought some sheets of clear acrylic and had them cut to the size of the riser platform that I wanted. Then I bought clear 3" and 4" acrylic jewelry store display risers (sorta' like these on eBay - Acrylic Risers on eBay), to place the longer platforms on top of. I wanted to use all clear material to lessen dark areas in the cases.
There are still girls in the back row ... but at least now they can see over the others' heads. (this is an old photo ... it's a lot more crowded in there now)