Wayne, what about a Lazzeroni Tomahawk or Firebird? The Firebird will push a 160gr bullet to 3550fps and the Tomahawk will go 3150fps. Not bad at all, and it's different.
But to the OP, I think a lot of the choice will ride on the game you want to hunt, as there is a bit of difference from pronghorn to deer to elk to bear, and they will require a bigger round as you go up in size. One important thing to keep in mind, if you have enough gun to kill elk and bear at 1000yds, then you can kill anything smaller at 1000yds as well. It doesn't work the other way, and I would rather have too much gun than not enough if I was shooting that long.
For deer and similar sized game, and even some larger game such as moose, a 7mm Mag from GreyBull Precision would be perfect. They have built an entire business around 1000yd+ hunting rifles that are super accurate, and they really know their stuff. Last time I checked, they only built rifles in 3 calibers, .243, .264 and 7mm Mag and use Berger VLD's for all their hunting and say they are the best hunting bullet going for long range.
If you want to hunt the really large game, such as the larger bears, elk and such, than one of the big screamers will be best. The Lazzeroni rounds have incredible capabilities, the .338 Lapua is obviously a great round, the Remington ultra mags and Weatherby mags are great rounds as well. You have a lot of choices to go with, and many rounds are plenty capable. You just need to figure out what the largest animal you will hunt is and go from there. And if the gun will be used mainly for paper, then you don't want to go overboard with a shoulder breaking, barrel burning monster mag that costs $5 a round to shoot.
It's all a matter of figuring out what you want to do the most and how big of an animal you want to hunt, then it will be easy.