First off: The iconic Spyderco hump-and-hole is just not esthetically pleasing to me. If Dr. Seuse designed a knife for one of his characters, it would look like something from Spuderco. I have one, given as Christmas gift from our son, so Its gotta stay, but . . .
Next in my not-for-me list would be square cut straight razor profiles, with sheep's foot blades coming third or so. Also not a fan of the angular, aggressive looking grinds with multiple cutting edges. Also not enamored of (gasp) "tanto" points.
I am attracted to the visual look of the traditional Ka-Bar or Navy Mark 2 fighting utility profile. A shorter 5" blade might be more utilitarian but might also spoil the "look" I like/ The bilateral symmetry of the various dagger profiled blades are also pleasing, though not anything I'd carry. The Randall, EK and Ralph daggers come to mind. For some reason though, the Fairborn-Sykes comando dagger does not speak to me.
A fantasy knife I'd like to see in series production might be a "King Tut" dagger made with modern materials without all the gold etvc . . .a usable knife costing less than a big house or Lear Jet.
As for a knife I'd like to actually own for usage, is one of the drop point hunters in the style of Bob Loveless. That would be nice to have.