I would first start with a 3M window film product applied to the windows. That would help with fading concerns. Next I would have draperies that would close so you can block out the light mount those on a wood rod that matches your floor. I do recommend the motorized wood blinds from Hunter Douglas ONLY.

Thanks. I hadn't considered a film and will have to look into it. Something like this picture is what I was trying to explain about roman blinds...

Those are not Roman shades they are just valances and will add color . I'll upload a photo if a sunroom from my computer of something you may like... Stay tuned!

Ok here it is...this reminds me of your windows and style.

Great space! the 3M window film for the upper windows is a good idea. You may also want to use the same blinds that you have on the bottom windows for the upper windows - if you need more protection from sun or for privacy. I would not use valances (as shown in the photo above) nor the curtains that go all the way from the upper window to the floor. It will only emphasize the height of the room. I would break the space in half by installing thin metal rods in bronze or gunmetal finish above the bottom row of windows. You can use some color in the drapes, perhaps, wine red (as seen in your blanket) to add warmth to the room. You will also need an area rug maybe in lighter gray (such as in your pillows) with red accents. Move the sectional away from the windows a bit so that it floats in the room and sits on the rug.