I take a different approach to a backpacking knife than I do to a camping knife. I prefer a light folding knife of medium size and I locate it on a lanyard around my neck. That knife, like my compass and whistle, on a separate lanyard, are never separated from me.
Some of my preferences include (and yes... I am partial to Spydies for backpacking) a Snap-It, Remote, Native, Delica or Rescue... each can be found between $35 and $75. I also like the 50/50 plain to serrated blades.
I've never found a backpacking knife task that required more than any of these any season of the year. With the advent of "leave no trace" backpacking you don't chop down trees or branches and do not light fires (carry a stove). Therefore most tasks include cutting; rope, tape, material, moleskin, bandages, blisters, and food. These knives will also filet fish (although not ideally as flexible as a filet knife), as well as protect you from wild animals and wilder humans.
Good luck whichever way you decide.
Stogie
"Remember... Size Does Not Matter (regarding backpacking knives)."