For a perfectly square table you may be tempted to use four matching pieces for a perfectly symmetrical look. However you can get a more intriguing look by using two pieces or groups one in each corner. Try a tall vase or lantern in one corner with a stack of two or three books in the other (and an airy sculptural accent on top).
Sometimes a coffee table that isn’t the standard height or width is exactly what a room needs. In this instance a very low coffee table creates a crisp horizontal plane in the foreground offsetting the long horizontal line of the credenza in the background. A higher table would have blocked the view of the credenza and competed with it; the varying heights add interest.