4throck said:

The concept art for Bespin had windows (see http://filmsketchr.blogspot.com/2014/12/freeze-your-at-at-off-with-star-wars.html ):

http://1.bp.blogspot.com/-QwCX6z88f_g/VIH151hoH8I/AAAAAAAAxGo/3E7DSPtWOIo/s1600/besp07.jpg
http://2.bp.blogspot.com/-rQM2ot1J2Ks/VIH18Qkps1I/AAAAAAAAxHk/zWa9O5AbOOA/s1600/besp18.jpg

So on this regard the SE is not adding anything 😉

Yeah, but it still takes away some of the tension and danger, and the symbolism of the Empire closing in onto the Rebels.