Fitting floor-to-ceiling double windows inside with blinds, any experience?

don't say that without having held a sample curtain up to a window before ;)
Before I clip those flimsy 13,- euro things to the window that constantly flap back and forth when you open the door, I'll try a curtain first.
Curtains are in my opinion the most underrated decorative element in the house. AND they also have a use o_O;)

As you wish, but I would rather replace the entire blinds with screens than clutter up these beautiful windows with such things...

I looked at the two photos from the original post again. I wouldn't mind 13€ ones, but I don't think double layering, meaning inside and outside, will look that great. That's why I would also try plain white scarves. Usually, a room visually benefits from some fabric and vertical lines. On top of that, it reduces disturbing sun rays :)

as you wish, but I would rather replace the entire roller shutters with screens than cover these beautiful windows with such things...