Keeping it simple
My EDC bag contains a Leatherman Wave because it works for me. It has a saw, knife, pliers, screwdriver, and it doesn't go over the top like some of the larger SwissArmy kind of knives. This is my own personal preference, and works the best for me.
Keeping items you are comfortable with is key in any kit. KMn04 is a very handy item to have for its versatility (Fire starting, water purification, sterilization/disinfectant, wound treatment and signaling), but does you little good--or worse--if you aren't familiar with how to use it properly for the intended task.
It's important to tailor your kit to your own needs, but here's some of the things for which I think are worth considering having a backup:
- Light source
- Map (if you carry a GPS)
- Batteries for everything
- Flashlight, GPS, Cell phone etc. (I really like having devices that use the same type of power source whenever possible)
- Pocket knife
- Fire Starter
- Water/water purification