The Fenix is a good choice but I also found a Ultrafire 1 AAA led light that fits in my BladeArt Mission Wallet. It appears to be brighter than the Fenix. I carry a spare AAA battery on the keychain. I used the plastic cover for a 75 ohm cable TV connector, a fishing swivel and some shrink wrap.

Cut a slit in the top of the cover just big enough to slip the closed end of the swivel thru the cover, rotate the end of swivel perpendicular to the slit. Friction holds it in fine. Shove the + end of battery inside the cover and seal a piece of shrink wrap around the battery and cover, this keeps everything safe and secure. You will want to shave the lip of the cover a bit.

I use the aircraft cable keyrings from CC. I cut a piece of 550 cord a little longer than the cable, stripped out the inner strands and heat sealed each end. I slid the cable thru the sheath. Makes the cable a little quieter and less abrasive on your fingers and gear. Use orange 550 to make it easier find. I also use electrical tape or shrink wrap on the items to quiet them and reduce the scratching of the paint/finish.

American Science and Surplus sells small pill fobs with a swivel and O rings that should enough tinder.

The CC titanium screw post carabiners are nice too. The peanut lighters seem to not to dry out much because of their O rings.

I find that putting fishing swivels, the kind with snaps, on the keychain items, makes things easier to take things off and keeps things from unscrewing themselves, like the ends of flashlghts.