After much trawling across the web a few years ago, I came up with my solution for travelling in remote areas (no electricity), you may find something of use in the philosophy although the hardware is now dated.
I acquired a Samsung netbook with really good battery life and about 300 GB harddrive, a small wireless mouse, plus an external WD Passport (500 GB), plus weather-proof SD cases and about 20 SD cards from various BH PhotoVideo sales. My daily bedtime routine is to climb into sleeping bag, put headlamp on, create a folder for the day on the netbook, and copy contents of the day's shoot into it. Then have a quick peek via Faststone Viewer to make sure the copy was successful, this is freeware and very light on CPU & memory (and I can't resist a look at the day's captures even on the crappy screen). Also copy the folder to the external hard-drive and do a quick check - number of images and folder size compared to the netbook folder. If the SD card is nearly full, lock to read only and put into the storage case. Mind you, I'm using a K5 and the cards were relatively cheap, so I don't need to reformat during the trip.
The Samsung lasts for at least a week without recharge (I've not tested for any longer) because I restrict its use and have removed all extraneous stuff off it. Lightroom barely loads anyway, so I'm not tempted to edit anything. I even leave the obvious duds for culling at home.
Yup, I'm paranoid about losing pics from places I know I won't be revisiting, but it works for me.
The netbook is quite useful for the odd email when close to the internet and electricity. Not sure I'd like to use it for a walking trek though, the battery makes it heavier than a tablet (about 1Kg I think).
So: reasonable weight, long battery life, dependable storage, at least 2 copies on physically separate devices, the comfort of viewing the images and easy to use (same OS as my desktop PC).