Going out with a bow and backpack is one of my favorite things. Kind of like the old Reeces Cup commercials when the chocolate and peanut butter gets mixed and everything gets better!
Before you pick a backpack, you really have to know what you're willing to be with and without for a week in the woods. A minimalist pack like a mid 2000 cc capacity might get you by, but most people can't pare down their load to those dimensions, esp if there is a question of packing out a big game animal. I use about 4000 cc in my Kifaru and most of my gear - tent/bag/stove etc - would be considered lightweight and packs very small.
Price is also an issue. Kifaru makes an excellent pack and is what I prefer. Another high end pack manufacturer that a lot of backpacking hunters prefer is Mystery Works by Dana Gleason. There are less expensive packs and many people have good results with backpacker/mountaineering packs like Gregory or Arcteryx and choose a neutral color scheme. You can buy these easily on fleabay, etc.
Of all the issues, fit trumps them all. I have a Gregory and a Mountainsmith in addition to the Kifaru. They fit me well. But I tried one of the original Dana Design packs when they were made in Montana and it was pure torture on my hips. A good backpacking store with an experienced fitting staff could help you narrow it down to a few brands and then you could pounce on a used one in the same model/brand if you did not buy new. Load the pack down while you're in the store and get the straps adjusted properly. You'll know if it is comfortable fairly quickly after walking around some.
If you get interested in this and would like a copy of the backpacking list I use for my CO elk hunts, email or PM me and I'd be happy to get one out to you.
Best of luck, it surely is a good time to be out with everything you need on your back and a roamin'
David