"...actually a revision of a design I had been thinking of initially for Iron Man 2 before ultimately choosing another project. It was a lighter, more streamlined version of what had come before, trying to integrate a flowing theme wrapping around the "RT" on the chest and mirroring that fast line through the body. This was more of the evolutionary design, and ultimately was approved pretty much immediately as a starting point for the Mk 7."
"The next design was playing around with the stance of the suit toward more of a brawler attitude, somewhat beefier and less aircraft-like."
"Lastly was a more extreme departure, trying to create a very different silhouette, sort of the Stark Industries answer to a more heavily militarized suit like War Machine, but drawing from Air Force form language instead of Army."