HY,
A few months I read the the newly manufactured 717 will leave the factory line without the small eyebrow windows. Boeing came to the conclusion that they´re not needed any more. I think it was all abaut visibility. But on the other end it makes the "face" of an A/C. I´ve seen many times pilots covering this windows with newspapers during day operation because the sun dazzled their eyes. So in my opinion the need is less than the side effect but it makes the planes distinguishable.
yours,