I have a Sturmey Archer XL FDD Dyno drum brake. It's over 11,000 miles on 3 bikes with not a speck of trouble, now with a Rohloff on tour. Not as good as a disc brake but Ok. My lights are never off now and plenty visible, even in broad daylight. Everybody notices them. Whatever drag it has is NBD. I haven't got around to the charging stuff yet. So maybe a flashlight would do when days are 15+ hours and not raining much. I've been needing them 24 hours a day here when clouds are low or it's dark at 5:00. Dyno's are the ONLY way to go. Opposing headlights will still blind you. I even did a mountain pass in the dark. Doh ... I'm pretty sure your batteries and charger weighs the same as my hub.

I have been using maps on a Samsung S5 in airplane mode in Vietnam. It shows the point where I am, sometimes slow. From there it is easy to choose the what to go. Could maybe go 2 days this way. I would never trust GPS zombie directions. So far my 6 ft paper maps are just passengers.