Justa' thought for you and probably a much less costly solution.... First, I'd use black wrought iron poles/rods for what I'm about to suggest. Think about using a rich, earth toned fabric (rust & lt golds..maybe in a paisley design? However wide your total window is..buy that much yardage...(based on 54" or 60" wide fabric). I'm seeing a canopy suspended down about 4' from the very top of the top windows. The width of the fabric would be the length of the canopy (w/perhaps 3" hems at top & bottom. Run the top of the canopy on a pole at the very top.Then.. by simply placing a pair of the black wrought iron 'L' shaped plant hangars at the 4' mark-you can run the bottom edge of the fabric's hem thru another pole & it will project out away from the window somewhat..I think you can get them w/a 12" arm. This canopy would then cover the top 4' of your windows entire length. From a person's view sitting on your furniture-you'll still be able to look up and out the upper windows-but the glare from the sun will be blocked from the top portion. Also I'd again-(a simple hem job)...make dummy panels to hang from the very top of the top windows-all the way to the floor...one on each end and one on the 2 center wood casings. The canopy would hide your short rods from which the panels will hang. Then to give you a soft look to the bottom portion...you could hang, say- light gold,tab top sheers or semi sheers,on yet another black pole, which would diffuse any afternoon sun. This pole would be placed, on the section of the wider wood beam (for lack of a better word..the one that's 2 glass panes above your sample blinds). Topping it all off would be some really decorative black finials on the ends of the 3 poles. Methinks it would just be a different approach & not something eveyone else has. The cool thing is-if you bouth the drapery panels all in 1 continuous length at Joanne's? You'll get it for the 40 or 50% off price coupon-just cut off the 4 lengths of the windows yourself.

Beautiful space. Do you get lots of light in from that window? The cabinets are dark and I think natural light would be wonderful so keep the coverings on the light side, not the heavy rich stuff of the early 90s. A window shade or curtain should have a bit of space. If you are buying something from Smith Nobel, JCP, Macy's or some such place they will have specific instructions for mounting. I do not believe it will rub the paint off. There will be a bit of damage to the walls as screws into the wall will need to be puttied when you take down curtains later. My favorite place for window covering is Calico corners... Have you visited a shop? They are so much fun. Here is a link http://www.calicocorners.com/ I like fabric as fabric can really soften a space. Although if you love bamboo or woven shades that can be nice too. Here are some visual ideas...

I would look at white plantation shutters for the windows and a Vertiglide on the slider since you use it every day. I would then either add a cornice over the Vertiglide or some drapery side panels. Now if you have young children I am going to change my Vertiglide recommendation to a vertical. I know no one like verticals but if you have sticky little hands, you want to be able to clean the blind easily! When they have grown to the point where you don't have to worry about that anymore, then you can move to a Vertiglide or something else. Here are some links to a blog you may want to look at for ideas. https://dressthatwindow.com/beauty-of-shutters/ https://dressthatwindow.com/i-hate-verticals-what-else-is-there-for-sliding-glass-doors/ https://dressthatwindow.com/drapery-side-panels-complete-the-look/ Not a perfect example but just trying to give you a sample of the combination of shutters, a Vertiglide and a cornice board. You can really dress up the windows on that back wall to look great! Good Luck!

It looks like there would be a better furniture layout but more views of the room would be needed to see what that is. Once that's finalized, an area rug would help to visually warm up the space. It would be easiest to purchase a rug before the art. As far as wall art such as paintings, I would definitely look for pieces with lighter colored backgrounds.