Hunting in my area (north-central Arkansas) is short- to medium-range due to woods & brush, and nothing bigger than black bear, which are usually sub-300 pounds. For our purposes, a heavy-loaded .357 magnum lever gun would suffice, running 1100-1300 ft/lbs with a lot of factory loads.
If I were somewhere that had longer distances or bigger animals, it would be hard to argue with 30-06.