Anytime you pack for a 7 day plus hunt I like systems that have built in versatility. I have an ultra lite 30 degree sleeping bag from REI that when in the bag is only about 12" in length and maybe 8" diameter and weighs 1 lb. Coupled with good insulated wear it works on nights when it gets colder.
I have a stone glacier grumman light down insulated jacket and the grumman down insulated pants. I also have a KUIU insulated vest that I take to because it doesn't weigh but a few ounces yet if I want warmth without wanting to wear a down jacket, I can toss on the vest. I used to think having an inuslated vest and a jacket was just stupid, but once I realized I could save ounces by going extra packable and light on the sleeping bag, and tent, I found that this system worked really well. I judge my gear based on how often I'm wearing it in a given day and with the exception of the insulated pants, I wore most of my stuff everyday. The pants are necessary though if you're going to gamble on the climate with a light sleeping bag.