"Nice to see you again, Mr. Sander. Please take off your shirt and lay down on the couch. The doctor will be with you in a moment."
This is roughly how I feel about the room. Too sterile. In fact, from the pictures, the only thing I can learn about you that you like computers. Aside from that, there is no trace of individuality in your room.
If you are against re-painting, put some large, colorful prints on the wall, gray color alone doesn't work. Also, there is too much fake wood around. At least, spread some carpets on the floor, or even better, put in some good quality laminate floor that will look and feel like real wood. The curtain should go, too. Use a pair of full-length curtains in a warm colour instead to cover those ugly wooden boards next to the window.
On a positive note, keep the chair, the MacBook and the desk lamp, they are cool.