Remember elk live in steep country and a lighter weight rifle can be nice. I also like a 3 position safety so the Winchester M70 or Ruger M77 are favorites for me. I really like the look and feel of the Kimber 84L but have heard mixed reviews. I like that these rifles lock the bolt closed in the furthest back position so when I switch my slung rifle to my left shoulder and the safety rubs against my pack it stays put. Tang safety's are nice too but some let the bolt unlock with the safety on, have to check the different brands. A light STIFF synthetic stock factory stock is always good especially if it has a good recoil pad like the Limbsaver. To many factory stocks flex a lot on the forend and I prefer a stiffer stock that stays free floated when pressure is put on it from a bipod or other rest. B&C makes a good aluminum bedded stock for a pretty reasonable price if the factory one isn't good enough.
For calibers I'd personally stay somewhere in the 270-7mm Rem mag range. I like flat shooting guns with light recoil. My personal choice is two rifles, a 264WM for plains and a 270 for steep country. Someday I'd like to have a 300WSM as a dedicated elk gun, but the recoil is to stiff for me personally to consider it an all around rifle. I tend to specialize rather than go for an all around though. The long barrel needed on a 264WM or most of the Weatherby magnums for top speed isn't something I want on an all around rifle. While I love my 264WM the longer barrel can be a pain in the timber when it makes the stock stick further over my head in the Eberlestock scabbard, or the barrel stick farther over my shoulder on a sling. I use a shorter, lighter rifle on the mountain and the 264 as a plains gun.
I'd prefer to stay in the 22-24" range and use a light enough recoiling round that I don't need a break on it for something I'll pack around a mountain. I have a flinch from shooting a 300win to much so the 7mm Rem Mag is about as much gun as I want to use. Even that is to much at times with the amount of practice shooting as I do. For me the top calibers would be 270 win, 270WSM, 280 Rem or AI, 7WSM, or 7mm RM for an all around rifle for Wyoming. I know many 30-06 fans will disagree with me for good reason, but if I want to step up to 30-06 recoil I personally prefer to go with the 7 mag and it's higher BC 160 or 168gr bullets that can be pushed to 3000fps.
Something else to consider if you choose a less common round for your primary gun is a common gun to take for back-up. For example if I'm on a hunt and somehow become separated from my ammunition I'm not likely to find a box of 264WM on the shelf. With a 270 as my back-up rifle if I get separated from my handloads I'm likely to be able to find some factory rounds to shoot.