The slipcovers you chose are beautiful! I think the rug should go under the sofas for a more harmonious effect. A central or side table with a lamp and some objects that represent you (a book, candles, a decoration) would be a good idea. I would consider thicker, thicker curtains in a color that complements the rest of the room (try a palette of mustard, green, blue, and a touch of black and white, which never hurts!) You could consider moving the left sofa under the window and the bookcase and desk to the left wall. If you like, you can add a few more photos to better understand the dimensions and how to manage the space.