I too like the beige color theme, but since you want to hang with the gray try reversing the highlight white with the gray of the "front" (rounded portion) maintaining the gray of the top bottom and "back". It lightens the look quite a bit, however, the white of LDD, at least on my monitor, isn't white white but rather egg-shelly. The green band I changed to beige and all in all it's pretty nice looking though considerably lighter in tone. Great building and I think the lighter tones will work in a city scape.
I also tried a sort of checker board effect maintaining the outside 1x6 gray brick grey and reversing the rest as described above. This gives it a more dark feel while maintaining the light tone and increasing the visual interest. Anyway some ideas there.