Great home and space. Looks really nice except for the window above the sectional. Does that window lead outdoors or is there an addition behind it? My first inclination would be to sheet rock over it and make that a wall-then you could add a beautiful painting above your sectional. Another option would be to add a modern roman shade to the window in a modern fabric.

Thanks Karen. The window looks out to a covered outdoor patio. It has a honeycomb shade that we always keep open to maximize the view (our backyard is thankfully very private).

Since it appears that you have so many windows and lots of light coming in, do you need that window? Just thinking you may want to think about having it covered in the future, so it doesn't feel awkward. I'm not sure what the cost involved would be, but everything else you do will be a temporary solution. Your home is incredible. I love the contemporary Midcentury Modern design.

It is the only window that opens, so we need it for ventilation. I was thinking of flanking it with curtain panels or maybe different art?

I was bummed to hear that you need to keep windows over couch for ventilation. My gut said dry wall. However please consider taking down flanking art work and keeping those areas free of anything. I think the art work pulls the eye to windows ( like 3 rectangles in a row). See if leaving them blank helps window fade from view.

We actually like the window because it gives us an almost panoramic view of the yard and helps the indoor-outdoor connection. Here is another view taken from the kitchen:

What a great space! You don't need to do anything with the knee wall under the windows. For the wall behind the sofa, I would remove the art from both sides, and put a much taller lamp on the table in the corner. Leave the other side bare. I would definitely not do curtains on that window. Just let it be what it is.

I changed my mind about the art. Wall looks really naked without it, which I don't mind, but I suspect you will think it's too bare.
Some very cool, tall, Blenko lamps:
http://www.rejuvenation.com/catalog/products/blenko-handblown-amethyst-table-lamp

http://www.rejuvenation.com/catalog/products/blenko-handblown-turquoise-carafe-table-lamp

Since you said you were perplexed about the window above the couch, I'm a bit confused as to what the dilemma is.... Truthfully, my first impression of the window above the couch was that there was an addition behind it. I agree with miacometlady-it would be great if you could cover it/dry wall it and place a beautiful piece of art there. But since you want to keep it, I would remove the art next to the windows, so you are not drawing more attention to it. The addition of rod over the entire wall behind the sofa with sheer panels (suggested by londonvon) would help camouflage the window.

I would say the hue or value of the white you have is off. The space has a lot of cold colors so the walls should follow. Maybe a real faint grey edging on the taupe side. Otherwise really great space. Love the light

Treat it like a window since it is. When you mention the half wall to the left of the TV are you meaning the angled windows which no doubt are original to the house?

What about the windows surrounding the open doorway to the living room?

I absolutely adore MCM homes. I'm going to suggest something very odd sounding to you, however if you try it & it fails, not much money lost.

I love the wall of windows! What about mimicking the trapezoid shape somewhere in the room? Almost everything else is a square.

Buy Lill lace curtains from Ikea. They are 110" X 98" and are white meshy net. They are $3.99 a pair. Hang them from just below the ceiling down to the floor on that wall between the art. Of course you will need to pull the sectional away from the wall a bit after they are hung, but not much. Leave your window open for the ventilation.

You will probably not even see that it is open due to the fullness of the panels. You will get air through them but not see through them much, if any. Cut the length to match the wall height (no hemming necessary). If it doesn't work, you are only out the $3.99. & the time involved & the rod. It just takes a skinny rod. They will look so nice you may want to add them in between the kitchen & the family room too.

to create a wow factor place those cheap shears from ikea to cover the entire wall behind the couch n across the window wall at the same height of the sofa wall. here's an example of what I did for an industrial space. place a tall floor lamp from ikea on the end table for added wow.

Great suggestion by londonvon to camouflage the window. White, gray, or even teal sheers/panels would be pretty in this space and would definitely create a wow factor.

Groveraxle, thank you for the lamp ideas, I agree that a taller lamp is a great idea.

One thing that may not be coming across in photos is that the view from the window isn't actually that bad. In a couple of weeks once the leaves and flowers come out, it's very nice.

Titothecat, the white wall is a more pure white (even slightly cool) than it looks. The ceiling is gray. The adjoining room is indeed taupe, but will become white soon!

Sandradclark and londonvon, great idea about the sheers. I would love to dress up the wall a little.

even w the shears covering the entire wall u can still place art in front of the shears just like the mirror I did in the pic

No no no. Don't drape the wall. Leave the window be. I see a clock through that window. That should probably go. Make the view through the window totally MCM. You could put a Nelson clock on the wall behind the window. Now THAT would be appropriate.

Just thinking outside the box - If you really like the view through the window above the sofa, perhaps there is a way to accentuate it? Make the window view somehow become the art/focus of the wall?