Creating a complete composition on a wall definitely gives you much more bang for your buck.
When hanging artwork or a mirror, think of the wall as a blank canvas. Create more impact and interest by grouping several items together. Formulate a composition using your wall space vertically as well as horizontally to become a focal point. For example, instead of hanging just one painting over the sofa and one mirror over the buffet, add more decorative accessories to the composition. On each side of a vertical painting add wall brackets to expand the composition horizontally, and place a vase or floral piece on each bracket to add height and interest. Over the buffet that has an existing mirror, add a small painting or print on each side of the mirror along with three small mirrors staggered over and around the top of the larger one to add verticality. A common thread to visually relate all of your items also helps make your composition have more impact - such as using all gold finishes for the frames of the pictures and mirrors. Look around your home for these decorative pieces that you may already have that are looking lonely where they are placed. Create an all new look for your home by forming your strong focal area and group some of your pieces together possibly adding one or two new items too.