if you are gonna walk long distance in it and have it weigh over 15 lbs, then i'd get one with at least a decent internal frame and both waist and sternum straps
this adds a bit of cash
mystery ranch packs pretty much all have adjustable frames and some others do too
this is very important so that the pack will fit you well
you don't need to use a hunting pack, a lot of hiker packs work well
the mystery ranch scree is my main pack and it is not as much as the hunting specific mystery ranch packs
Your next wilderness destination awaits, and so does the pack that’s going to get you there. Streamlined for hauling only the most essential gear, the SCREE 33 stands ready to get you all the way to the top…and back again.
www.mysteryranch.com
with some of the hiking packs, you might want to cut off the metal zipper pulls and make your own out of cord so that they are more quiet
if a pack doesn't have the exact straps you'd like to tie stuff down, you can make all sorts of temporary tie downs using bungees and webbing....can put them exactly where you'd like usually and not even have to sew or modify the pack