I've been pretty traditional in pack usage - an external frame, preferably with a yoke suspension system - and a single, large pack bag with a few side pockets. Maybe 4-1/2 pounds empty. Sure, I've got 1-pound packs, but by state law and for ethical reasons, we need to pack out all edible meat and the meat of two caribou or 2-3 bears is a fair bit for 2 or 3 guys to carry so I want a good frame and suspension system.
My UL mods have been in the tent, sleeping bag, clothing and cooking gear - all that stuff you carry BEFORE you make the shot. BEFORE you make the shot, you're humping all over the place - for us, either roadless bays off of Cook Inlet or a grass volcanic island in the North Pacific. AFTER you make the shot, you pick the most direct route back to the truck/boat/four-wheeler trail. with 30-40-50-60 pounds of meat per person.
My usual role is "sherpa" - for reasons of marital harmony, I don't pull the trigger. My hunting buddies are really happy to have someone along who like to hike. Very first thing, they'll carve off a quarter and give it to me to carry back. I've done as many as 3 round trips while they are butchering and deboning, so by the time the animal is all dressed out, we each take one last load and we're done.
Advantages to that system are that I get the miles I like, and no one leaves the carcass to the wolves/bears/foxes/eagles. Everyone is busy, being productive at all times. Standing around is for afterwards around the campfire, not while a carcass is still warm.