A rug….

Shift your desk a tech to the right and/or pull your leather chair and ottoman forward into the space more. The vertical blinds over the desk are pretty tough - take them down and put up a rod that is wider than the window to echo the roman on the french door - like http://www.potterybarn.com/products/peyton-linen-cotton-drape/?pkey=ccotton-linen-drapes. If you need more privacy, add a woven wood behind it in a dark tone.
Something pretty on the floor (floors are gorgeous in their own right) but I see the green in the art - http://www.potterybarn.com/products/gabrielle-rug-green/?pkey=crugs-by-color&cm_src=rugs-by-color

I like a rug in the style judyg posed and agree about the window treatment. A natural woven shade or white plantation blinds are nice for privacy and I would get a rod so your drapes hang wider than the window. Will probably obstruct the pictures so maybe move them over the couch.

Consider panels on the windows - floor to ceiling, and then move your art to over the sofa and also a rug. Moving the desk to the right may impede opening that door but it would be nice to bring the chair
and the ottoman over a bit so it feels more part of the room. See below. Choose a rug you love and then pull a colour from your rug for your panels.

Your room is very monochromatic, could a splash of color be what's missing? You have a small amout of green in the pictures and the item under the table. How about a large colorful picture/painting on the wall above the couch, accent pillows on the couch and drawn together by curtains or a simple valance on the window.

With new romans to match door

I applaud you for having your office in the FR, you must be very organized :-) I wish I could be that organized.

This is the rug I would use to match Carolyn's suggestions

I would also go for smaller decorative pillows on the sofa , and a more textured one on the wing chair in a darker color

What is in the area that we can't see? Another wall or room?

Perhaps remove the round central table and replace with a low dark thick square center table of a shade approximate to that of the office desk against the photo's rear wall.

HI - Anna -- Can you try your desk in front of the roman shade window so your back is not to the room . Then pull that leather chair more into the room . Or at lest turn the desk so your back is to the roman shade window . Then have some nice drapes that fill that whole window wall to full height.in a white . Move the two pictures maybe over the sofa - 6 inches between sofa back to bottom of frames .The vertical blinds are more suited to an office building . A beautiful ethnic area rug with some rich colors will ground the room. Also adding some pillows with more rich colors like maybe a teal . I love the polar bear , put him on the coffee table along with a few other items like a nice colorful bowl and a few stacked books or a decorative box for your TV remotes .

lefty57, come say "hi" on OLLD 3/8.