Whats a good all around caliber for Wyoming?

.300 win mag for the animals you listed, but switch to a .30-06 if you plan to hunt deer.

I would lean toward the .30-06 because it has a bit more power than the .308 especially with heavy bullets. The -06 with 150 grain bullets is great for antelope & deer, Use 180 grain and heavier for elk, moose, and bear. It will even drop a bison with the right bullet. Plus, most places where you buy ammo will have -06 in stock but may not have the 7mm or .300 Magnums.

That would actualy be 2 calibers ---- A .270 and a 30/06 ----- See Below....

http://www.chuckhawks.com/perfect_pair.htm

Like you I do like the .308 but realize it may not be for you. The animals here in New York State are not as big and the spaces are not as wide open as you have out there in Wyoming so the .308 works well for me. The 30/06 has a little more reach and more knockdown power than the .308 but has been argued to be a little less accurate over long distances. For hunting with the 30-06 use top quality ammo for good shot placement..... For smaller critters use the .270... I know budgets can be tight but for your area of the country 2 rifles may be better than one....

300 mag should be on top 7mm right behind 30-06 layin back and 308 at the bottom

30-06

06 should be more than enough for any game you have listed....7mm or 300 mag would be better but an 06 will work fine