Consider replacing ordinary door hardware with more stylish options. Handles and knobs in Lucite, modern brushed brass or polished chrome could give the room an updated feel. For a more cohesive, intentional look, coordinate your door hardware with your drawer pulls.
Whether they lead to your closet or your bedroom, doors need clearance to open and close. The required clearance may limit your options for furniture placement and size. If this is the case in your home, consider replacing traditional doors with a stylish folding, sliding or pocket door. These take up less room because they eliminate the swing action of a more standard option.
Similarly, window drapery can be hung from the ceiling instead of on the wall just above the window. Hardware for most window treatments is designed to be flexible. So try turning the bracket up and installing it on the ceiling. The length and vertical lines of the drape will make the ceiling feel higher and the room larger.
Use multiple mirrors on a wall in the place of art. A gallery of mirrors in different shapes and sizes can serve as a wonderful feature wall while helping the room feel larger. Or try placing an extra-large leaning mirror against a wall. Its dramatic size will make the room feel immensely larger and brighter.