This link gives a DOB from 1949-1954 for the I-70 killer. The comments are interesting.
http://unsolved.com/archives/i-70-serial-killer
Then this link states the killer is mid 20's-early 30's.
http://unsolvedmysteries.wikia.com/wiki/Interstate_70_Killer
I do see a resemblance between the composite and NF though and he would have been in his early 20's at the time of the I-70 murders. Not sure of NF's ht. but inferred from comments by coworkers at Hoover Dam on FB that he was a small man and the ht of the I 70 killer is 5'7"-5'9" so the ht fits. The hair color is similar also.
One other thing that has been bothering me about NF is he appears to have a messed up left eye and a redness to the left side of his face. Has anyone else noticed this? Anyway, One of the comments at the first link I posted mentioned the I-70 killer had a messed up eye. Here's a link with a pick of NF.
http://www.washingtonpost.com/news/...er-may-have-slain-a-serial-killer-police-say/
MOO
The first link does have very interesting comments. In fact, the very first comment took the words right out of my mouth. The hair of the man in the composite sketch looks identical to the composite sketch of the murdered girl in Michigan that was discussed upthread here. The resemblance to Falls is pretty strong. The descriptions of this person's alleged behavior and weirdness seems similar to how the prostitutes in W.V. described Falls as acting before he attempted to murder Heather.
About his messed up eye.....could that be due to his dental issues? I remember reading earlier that while he worked at Hoover Dam, he was not usually put around the public because of his poor dental hygiene (one reason, anyway). At the time of his death he had dentures. So when these murders occurred, as well as his time working at the H.D., he would have had continuing dental issues. Wondering if he had issues with abcesses, etc that would make his face red and puffy.