Setting up a display on your shelves is one of the more overlooked styling challenges people face.
This is a console table that I recently styled. I like to work with like items - glass objects, white, sculptural pieces, metallics, greenery, and books. Find visual balance by placing like items on opposite corners. Stacking books (with covers removed) and add lighting!
Of course, there are a million ways to style shelving, so just keep working on it and changing it up. It takes time for you to get the right mix of items that feel right and are also meaningful to your space (and that plays a big roll too!)