I've been reading this post for awhile now and figured I'd contribute.
I was bored messing around in AutoCAD Revit in class and decided to make a pretty-close-to-scale model of 1 WTC.
Here is the current cross section, (assuming a height of 830 feet, which might be a little high)
From this geometry, I estimated the main tower section is at about 52%.
I love the profile and the look from straight on one of the sides of the base square:
However, at a 45 degree angle, the building has a pretty ugly profile. It's kind of squat looking. There's not many images of the profile at this angle, so I figured I'd put it on.
As I said, this model is pretty close to scale but not accurate. It's just made from dimensions that I've commonly seen.