IIRC, 18/36 was hardly ever used because of the winds, plus you had a pretty big set of obstacles not all that far from the approach end of 36 (terminals, parking garages, the Hilton...). They cut 14R/32L because the part of it south of 10/28 ran into the construction zone for Twy N and the future 10C/28C construction. I may be wrong here, but cutting 14R/32L down didn't really hurt existing ops all that much...if they landed 14R they had the option of LAHSO if they were landing 10, and most of the takeoffs on 32L came from T10 north of 10/28 anyways.
Another question becomes the decision to get rid of the 14's vs 4L/22R. From an active intersection point of view, they all would've crossed 9R/27L and 9C/27C (once the 9R/27L extension was completed). To me, 4L/22R seems under-utilized...you don't land 4L, you only take off from it when you're landing 9R/10/4R, and you don't land 22R nearly as much as you did because of 27R opening up.