I settled on a Zebralight H31, I went CR123 as I use a Steripen so batteries can be swapped if need be, it has several settings- the medium setting (actually M2) is more than adequate for trail hiking at night, at that setting you get almost 23 hours of light

it also has a retina burning high setting of 220- not really sure what you'd use that for, for around camp the L1 (5 lumens, 3.7 days) or even the L2 (0.5 lumens, 21 days!) works great
it's still pretty light @ ~ 2.5 oz w/ headband and battery
I'll be carrying this lamp for upcoming R2R2R run of the Grand Canyon, we'll be running ~ 2.5 hours in the dark in the morning (and hopefully not at all in the night!

)
if I don't really expect to use the headlamp (vs planning on hiking in the dark) I often carry the diminutive (1.0 oz!) Petzel e-lite, it's plenty of light for around camp and in a pinch could help you get down the trail
this is at 3:00 AM, we're making a looong 28 mile day hike and needed a head start

the H31 was outstanding on the medium setting fully lit up the trail, you'd often forget your hiking in the dark.