A few years ago, it was all about contrast........finding window treatments that contrasted with the walls and maybe tied in some of the accent colors in the room. You can still see beautiful rooms that do use a certain amount of contrast, but the look that is more 'popular' right now, is something not that far off from the wall color. Something that works, rather than something that 'pops'. Now, for an accent pillow or a vase, you might want to have something that stands out. But for your windows, I think you may tire of fabric that stands out too much. I've had years to come around to this way of thinking, but I'm really liking the blended look, or even a smaller degree of contrast. Your test drape is not a bad color at all, but perhaps too shiny or dressy for the rest of your space? And I don't love the grommets either. In my opinion, they don't mesh well with the drape fabric.

In my recently redone bedroom, I've hung (natural colored) canvas drop cloths from clip rings on a 1" rod. They can be purchased very inexpensively and I love the look. Google "drop cloth drapes" and take a look at The Lettered Cottage, or Homebody Holly. Good examples of this look. Another possibility I see for your room, is something with a design or print, and the wall color, or something a little darker, as the background. Also, you are right on track with hanging them high to make the most of your great sliders.

Another spot to look is Cote de texas blog. Today's photos have some of the types of drapes that I can see in your home, you see how the blue room has drapes that are striped with the blue and the linen color. A little contrast, but not that much. And later, the pink drapes match the upholstery in the room. Both these looks are way too pastel for me, but maybe you kind of get the idea....

Red

Here is a link that might be useful: Cote de Texas, the Albans house

Tanya, I'm sorry but I don't care for the color nor silky fabric and design in the panels with your furniture. A textured heavier fabric would be better, keep searching, IMO no polyester for the panels. Are you considering an area rug??? JCP has some grommet contemporary patterns that would be my choice, they would give you some color.
HD Alouettes would be a vertical sheer, that would work great for all your large windows and doors too.

Definitely want a large area rug but we have a Shihtzu in training for now LOL!
I value your honest opinions as I can also share with my husband. These doors are on the west side of the house so it gets hot.Eventually a covered porch will be built and help with that.We have had the blind co. sales people come over and show us their wares. One salesman I was so NOT impressed with. He was gaga over the honeycomb blinds. I asked What they were made of his answer,"I don't know"
I asked "are they insulating?" He answered. "I don't know." I asked "how do I clean them?" You guessed it he didn't know.
Then he showed me the ultra thin bamboo shades. Does he have any idea of how many toothpicks my dogs could turn a bamboo shade into?
I also agree the walls should be darker but my dear son painted them for me right before Christmas and was sure lighter was better.Maybe I'll slowly change the walls,,,,one at a time so he doesn't get upset.LOL!

That is a huge amount of window space - and lovely! What I think you have to consider is that when you open those drapes they will stack back to cover much more than just the drywall separators. It is also going to have a huge amount of impact on the room, and with everything else in the space in some shade of beige, any drapery with strong color or print (such as red) will become the focal point of the space. Which may be part of the reason you haven't liked any of the reds you have tried.

I would rather see you use some vertical panels on tracks, that could stack neatly and not overwhelm the window space or the room. Penney's sells some.

But, if you do go with drapery panels, consider mounting the rod on the ceiling to bring some height to that side of the room. Something neutral and textural, such as a burlap or linen (or something with that look), would be lovely imo.

Me? I would install a really cool fabric valance to run above all the doors, perhaps in a great botanical print, and then have the windows treated with the tinting to take care of the sun issue.

Also, check Penney's for some area rugs that are not expensive, and are washable. I think they will allow you to bring in some color and warmth that way. One larger one in the seating area, another under the dining table.