Re: paring knives. I had posted the paring knife. It is light, inexpensive and *sharp*, but best for kitchen and light cutting chores like trimming a piece off your pack or cutting line.
There seem to be several brackets for knives-- heavy duty tools that are more on the survival end of things, general purpose knives like the Swiss Army or other basic folding knives, or light-as-can-be cutting edges, like the small blade in a Micra tool or the paring knife. I keep a single-edge razor blade in my survival kit as an ultra light and ultrra cheap cutting tool. Others have suggested scalpel blades as they can be hafted onto a stick for a small spear or knife. Why not one of each?
If I were going to use it to split wood or other heavy duty tasks, then I would want a fixed blade. The weight issue with a fixed blade is that you immediately add the weight of a sheath. I don't know of any folding knives that I would want to use for prying, splitting or other tasks other than straight-away cutting.