Trigger:
Jack O'Connor was sometimes lonely at first in his crusade for the .270, but it's stood the test of time. It's a great round, depending on what you hunt... I use it as my #1 caliber for now, but that's another story.
Were I to start from scratch, I'd pick the .30-06 or maybe, just maybe, the .308 (incredible inherent accuracy), and I wish my favorite rifle was the former. Not because I dislike the .270 or lack confidence in it— I don't— but because '06 is just more versatile. Bullet weights from 100 (?) to 220 grains. Close enough ballistically, and more efficient, than 7mm mag (another good choice, btw). Like '06, .243, and .308, you can find .270 ammo just about anywhere if you don't handload or need some, like in Africa. I've used 140gr Trophy Bonded bullets with excellent results on elk, though some say .270 is too small for the elk. Mine didn't think so
Craig Boddington, one gun writer/hunter whose judgement i trust, picks .30-06 as his #1 caliber choice for
all-around use in N. America. It isn't the best at any one thing, but good at the most. If you're mainly a trophy elk hunter, I'd move up to the .338 or at least .300WM/WSM, and maybe even .375H&H if you want to have dangerous game capability too. Ross Seyfried, I think iirc, picked the '06 as his choice for an African light rifle.
There are of course soooooooo many choices theses days, mostly to sell new rifles and dies, and appease peoples' short attention spans. I don't gravitate to the really esoteric wildcats, like the Lazzeronis etc, but i'm more conservative. Many of the super magnums like 7mmSTW are great in theory, but you pay some penalties... recoil, noise (esp w/brake), barrel life, and really, I don't care if I have a ton of energy left at 500 yards! If i can't get closer than that, well, the critter wins that round.
I would love to have a .257 Roberts (AI maybe), a 7mm Mag, a .240 Weatherby, a .300WSM, a .308, a .375H&H... Someday. So, you have to decide what your mission is, and which calibers you'll eventually own, and think about integrating them. I like the idea of the new .300 win short magnum, and short action calibers in general, but haven't shot one. I know the recoil is a step up from '06, which can be stout with 180gr bullets in a light gun. .270 recoil is downright pleasant.