The treatments you have up right now work for opening the windows, which has to be considered, too. If you do not want them bare, as deco suggested, would just a panel on each side work? Just there for a decoration, sort of???

Looking again and I think the idea of bare would be best, as the water cooler is right there, too. If you need privacy, maybe take down the top and only put a nice and airy one on the bottom part.

Hi, How about this? you can use open, closed or semi-open, according to your needs of light and privacy. It's not expensive and it's modern.

Take them down, leave the window bare and see if that works for you.

Lift courtans would make it looks modern.

How about a simple grasscloth light-filtering window shade hung right at the ceiling trim? You can still have light when the shade is down, and you can see through it. Plus it lessens any glare from outside. Treat the whole set of windows as one window with one shade.

I think the blinds loredeco suggested are a nice idea. For another softer look you might like Roman blinds. That is a lovely outlook and you are fortunate to have such a nice large window.
http://houzz.com/photos/165042

I think crisp white pinch pleat style café curtains (no valance) would be a contemporary update to your style.
Something like this would be lovely...

I would go for a large roller blind which gives u the benefit of leaving most of the windows bare but gives you the option to close should u want privacy

I agree with Darzy. That pinch pleat style gives it that modern, tailored look.

This look went out in 1950. I would do pleated shades in white. Lowes carrys them and cut to fit for free. Paint trim white.

New light is in order something in brush nickel with white, . Lowe's also carry s this. Hang 35" above table. Use regular bulbs not the curly type. Paint all trim white and walls a dove gray, for a more updated look. On other windows you can do the same look but add white woven linen look panels on ends of window only. Floor to ceiling. Use a brush nickel rods.

I personally don't like bare windows even when I lived in the middle of the woods. (Anyone-could-be-outside paranoia, maybe.) How would it look if you treated it as one big window with airy curtains that opened in the middle and could be pushed back to the sides when opened? Your post was over 1/2 a year ago. I wonder what you did... :)