>>595057that looks like a great 3 day pack. small belt for comfort, fairly high riding, and enough room for bag, tent, pad on outside, and all the food and extras you need.
it is probably a little bigger than my rush 72 but wise, but mine has side pockets that make it wider.
50l is about what i try for on 3 day trips. i could probably do less but a 2 or 3 day trip is for comfort, not miles.