First things first, my pack weighs 34lbs, so I'm no ultralighter. I pack in Alaska so I can’t safely spend nights under tarps with little to no safety equipment. The mosquitoes, bears and even some moose are a real threat.
For a knife, I carry a real knife. The risk of cutting myself with a non locking folding blade, or some micro contraption made with a razor blade, far outweighs the extra ounces of a fixed blade knife.
I now carry a Fallkniven WM1. It has a 2.8 inch blade and weighs 2.5ounces. The sheath adds 1.5 ounces. When I need to cut, whittle or even puncture a can, this knife can handle it.
Another option would be a Kershaw Chive. It's a small locking folder that weighs around an ounce, and, it's a real knife that you can safely use without the risk of slicing your hand or fingers open due to accidental closure.
When it comes to 'stupid light', knives are at the top of the list for an accident waiting to happen.
Just a thought.