Here is a list of the best picks for lights, imo (weights with batteries)
Fullsize
Zebralight – 1xaa or 1x123a ~3 oz.
Princeton Tec Remix pro – 1x123a ~2.5 oz.
Midsize
Princeton Tec Byte – 2xaaa ~2.25 oz.
Fenix – H51 1xaa ~2.25 oz.
Ultralight
A3 EOS – 1xaaa w/hat clip- ~.75 oz.
photon freedom w/clip – ~ .30 oz.
Pick the best one for weight/runtime/function. The photon has a pretty minimal amount of light. All the others have similar output I think. The difference between the 70 lumen Remix pro and 200 lumen zebralight is much more drastic on paper than it is in the real world.
I chose the A3 EOS because it is light weight, and has pretty good output on high when needed. If you really need alot of output for extended night hikes, then the zebralight would be hard to beat.