Our platform bed is not very solid, but I love the way it looks. The support is weak, so I guess the mattress caves in too much. As a result, I get a backache almost every morning. In the interest of keeping a good-looking piece of furniture, and to keep from buying another set, is there anything I can do here? I was thinking about buying a big sheet of plywood the same size as the bed. But won't that cave in too, without enough support underneath? I also am considering just layering some bricks under the bed so they can support the bottom of the platform. Any other ideas?