How about large wood louver blinds with a crown molding valance placed higher that the actual window to give the feeling of height... color on the walls would be phenomenal.

I thought of shutters also, wide ones, but the window openings might be difficult to get to; I might choose the sliding blinds with a textured fabric which can be adjusted and have a valance to add weight at the top. Color on the walls would help. I can't tell what your style is elsewhere....

I like the lines of the windows very much with their variation. Did you change the size and placement, or replace to size?

What is the use of this space? Is it a living room, family room... Do these windows look out to a view? Can we get more information on how you plan to use this space?

It looks as if the ceilings are not particularily high in this room, so you might want to consider hanging side drapes from the top of the wall, touching the ceiling, to the floor. I don't know the overall look you want, but this often makes the ceiling look higher and the room look bigger. If you want to have shutters, you can have sliding ones that go from ceiling to floor that can be pushed to the side in the day time for the view or additional daylight.