Bulldog,
You've asked a technical question without providing data so we can help you out.
Hot, Hot Hot, for me means water hydration. If you've never hunted with a camelback hydration system (or similar product) you're in for a treat. The Camelback's ability to supply you with small sips of water by sucking on a tube is far superior to reaching for a canteen Look to around 100 ounces of water. You'll realize less leg cramping by staying hydrated and the tube system of sucking reduces movement, translate game doesn't see the movement so often.
Next, you haven't told me how long you're staying out? Are you hunting out of your car trunk or are you bivoacing for a few days?
A key decision lies in the desire to have an internal frame or external frame pack. Externals usually allow you to carry more weight farther but the internal frames sure are comfortable.
If you're staying out for a few then 2200 to 2800 cu inches will be comfy. Staying out for a week or better, with a shelter and now you're looking at 4500 cu inches.
A simple day trip should be accomplished by a quality fanny pack. My favorite setup for a day hunt is the Badlands Monster Fanny and a Camelback Hydration pack joined together. The Badlands Monster Fanny is about 1100 cu inches, enough for basic lunch and supplies, a knife, rope, compass etc., maybe even a few game calls.
Most people have a tendency to pack too much of worthless items they probably won't need. That John Rambo 15" survival knife with the hollow handle and fishing hooks is probably nice to have
but chances are a small blade of 3 inches will dress your game nicely. The signal flares and satellite link w/ NASA gizmo might just take up space and bog you down with weight that just tires you out.
Do you plan on packing game out? If so a skelton Freighter packframe might be best, with a small bag atttached for lunch and essentials.
If you're looking for a name dropper: Eberhart, Schuh, American Bison are quality packs. The Kifaru line has a good following. My personal favorite line is the Badlands products. I personally own and use are: the Badlands Monster Fanny (1100 Cu In), the Badlands 2200 (2200 cu in) and the Badlands 4500 (4500 cu inches) Do you see pattern here? Each level of pack is twice the size, depending on how long I plan to be out. No matter which pack I use, there is always a water hydration bladder with me.