I believe that it was Jack O'Connor who said: "Beware the man who only owns one rifle. He can probably shoot it!" This warning was valid in the old days when men did lots of hunting and had to kill lots of game, maybe to survive. Today, the vast majority of our shooting should be on the firing range. The chances to hunt, for most of us, are limited. Therefore, keeping detailed range books is a very valuable asset. If one views range work as an extension of hunting, same can be a lot of fun, while at the same time, getting one ready to take the world class trophy that may even be presented somewhere in the future.
That said, work up any number of loads and/or run any number of various factory ammo through your rifle, in order to find out how each functions in your rifle barrel. Keep records so that you will know which cartridge to use for the game, determined by the size and toughness of the game sought. If you later decide to jump to a second or third choice of load in your cartridge, do so with plenty of time to get back to the range and again test that load so that your rifle is registered and you are ready to hit the target at various ranges, from various shooting positions.
Personally I would take a heavier bullet over a lighter bullet, because I believe in creating a large wound channel. This, more important on elk and heavier game, as previous responders have pointed out that varmint type "Ballistic Tips" will cleanly take white tail deer, while the same bullet may disenigrate before penetrating deep enough into a bull elk to be effective!
Most lighter bullets can be made to exit the muzzle at a higher velocity, transmitting into a flatter trajectory. How far may you need to shoot? In the eastern woods, a 200 yard shot would be rare. In the Rocky Mtns. one must be ready for at least a 200 yard shot and prepared for a shot out as far as one is capable of killing cleanly.
Bottom line: Too many variables to restrict one's self to one cartridge, when one is anticipating hunts on game ranging from white tail deer to elk. Get at least a couple of cartridges registered in your range book, so that you will be ready for whatever hunt comes your way.