Hi there!!
I am not a night time cyclist, so I will leave that part of the discussion to someone else. I do all my mountain biking in the light of day, although night riding is something I want to give a try. As far as camping and night hiking here's how I look at it. First of all, if I'm are doing "civilized" camping at a camp site... I can pretty much go HOG wild, bring whatever I want to horde at the site and stowe it at base camp. That includes 12V SLA HID spotlights, too for seeing stuff WAY out. From there, night treking and overnight excursions from base camp weight and efficiency become more paramount. I limit myself to single AA and 18650 lights.
Headlamp is a Zebralight H501, its floody enough to be used as an area lantern or I can wear it around my neck. Eneloops work great in this light.
For hand held duties I bring one bomb-proof P60 host and stowe 2-3 P60 drop in module pills in my pack. That way its light weight, easily packed and I have redundancy. Host is a Surefire 6P, bored for 18650, with a shatter-proof polycarbonate lens. The tailcap gutts have been swapped with an over-ready zero resistance mod, that way theres no switch or spring (or anything complicated) to fail. Its just a brass "slug" in the tailcap that touches the battery tube to activate the light. P60 module pills are multi-mode DIY builds... MCE-2.8Amp, XRE-1.4Amp. I only bring one reflector though. The brass pills are inter-changeable, practically weight-less and don't take up that much space. My absolute SHTF 18650 failsafe is a Malkoff M60 for backup. I pack these with foam in a small plastic zip-lock food container. Using P60 pills and one bomb-proof host can pack 2-3-4-5x the redundancy (whatever I can carry) in a smaller volume and less weight than packing multiple 18650 lights. The drawback is if something does fail, I have to take the host apart in the field.
I also have a Fenix MC-10 I will use as a kind of lantern / flashlight combo. Its versatile enough to cover near-field flood if the Zebra should fail, and can throw longer distances too should the 18650 host fail. It tail stands and I can flood its light to wherever I need it, in lieu of a lantern. It runs optimally on the same eneloops that the zebra uses.
The other thing too I have found is I just don't really need more than ~250-300 Lumens... I mean yeah its nice to have more, but at the expense of weight and volume? Its a trade-off that I have not seen the value in. Same goes for far-reach thrower. I had an XRE Tiablo A10 I used to bring, and I just never really used it for anything other than Oooh look at that tree at 200 yards, ooh nice beam in the sky. (but thats just me, opinions will vary widely)
Some pics for fun!!
If I really wanted to stream-line things I could ditch the 18650 setup and go all-eneloop. Not a bad thing to do, eneloops are GREAT cells. I can still almost get my ~250 lumens if I use the Quark XPG-R5 with the Fenix at the same time. (FWIW I have never actually used this setup in the field... I'm too psychologically attached to that surefire-18650-DIY setup).
Good Luck with whatever you chose!! and enjoy the outdoors