Brandon,
I use both a back pack and a fanny pack depending on what sort of hunting I do. To be honest I have lots of packs. Big ones, small ones, fanny packs, belt packs, day packs, rucksacks etc. I am a sucker for a cool pack, bag or other. I have two that I use frequently. I have a pretty good size back pack that I can stuff with extra clothes and my ghillie suit. I have a buckle-on quiver that goes on it and my hunting chair also straps on the back. I use this when I will be moving around to multiple places, or have a long walk in to a sitting spot.
I have a fanny pack with shoulder straps that I use when I am going to hunt a treestand. It is pretty good size and holds everything I need. It also has straps on the top and bottom to lash down spare jackets and other clothes.
Sounds like your hunt may be a spot-and-stalk type of deal. If you go with the fanny pack, I have a tip to pass on to you. I have always had trouble with waist belt type fanny packs slipping down around my hips. I spent as much time pulling my pack (and my pants) up as I seemed to hunt. I bought a cheap pair of wide suspenders (camo with spring clips) and put those on the webbelt of the fanny pack. Now I don't have to keep the belt tight and it stays up.
What really seems to be the point is, how big a bag do you need to comfotably carry everything you might need on the hunt. Hope this helps. Good luck on your hunt!
OkKeith