Facinating subject.
I have done some training in Systema amongst other martial arts.
Both Vladimir and Mikhail (The two top instructors) have commented that a knife a person uses tells you a lot about the mind of that person.
Basically the more twisted and evil looking the knife. The more screwed up and twisted the person!
(I am not quite sure I fully agree. But then I love my Vaquero

)
I am a Psychologist (when I am not having fun in the Military) and I would comment that blades often mimick the shapes found in nature.
For example a leaf shaped blade (take the Bob Lum chinese folder) looks symetrical and harmonious and doesnt usually intimidate.
However blades which look like beaks, claws, spines, thorns, stings, Jagged serrated things (Things which are dangerous in nature) seem to act as a type of archetype which triggers the fight or flight response in the observer.
There was once a great post here about the most intimidating knife design.
I remember the Spyderco Civillian, The Vaquero Grande and a number of Jerry Hossom's pieces all scored highly!
A 17" Ang Khola is quite a smooth recurve and would scare the hell out of most people (recurve blades are a bit sting / snake like. Or maybe its just the size!)
This is an interesting topic for martial artists because the design of your blade may
A) scare the hell out of someone so they start running.....
B) Make them so afraid they then fight like a cornered tiger on a surge of adrenaline.
There have been a lot of posts on how the appearence / name of a knife can effect how the Police / court views a knife. This also effects how the sheeple view them. As we all know a scary looking blade isn't really any more dangerous than a plain looking blade.......
All is perception.....