If you seek the best survival knife, you must study those who have gone before, grasshopper.
Begin with Otzi, the oldest forum member. His was a flint blade with an ash handle in a plant fiber sheath, seen
here.
Best features-state of the art materials, constructed by the owner (maybe), could be resharpened (he had a retoucheur with him made from antler) reproducible by the owner if damaged or lost using available natural materials. These are the ultimate desirable features in a survival knife.
Second best might be a purchased knife that the owner has modified to suit exactly the favored survival scenario-( see the Everybody's Knife Book in the Lending Library).
Least desirable survival knife: one that some evil marketer has touted as making the owner taller, stronger, smarter, faster or tougher. Knives do not do this.
That said, knives are also works of art, fashion accessories, status symbols, totems, mood elevators, tools and , for the moment, relatively unregulated: get a knife that makes you smile. There are several knives in the image gallery that I find comforting to look upon-consider one of those. Like most things in life, the spiritual value is in seeking the knife, not finding the knife.
Om mane padme hum....