It depends on whay your aims are. Do you want just the guns that you need or do you want to build an arsonal? The 270 that you have will cove everything you mentioned very well. There would be very little point in a 308 as it won't do a thing that your 270 won't do just as well. If you want to spend the money on another rifle then the 300 WSM would make more sense. This even though the 308 will do about the same job out to 300 yards. I hunt and fish with a guide in northern Sask. He hunts birds, small game, elk, moose, bearand deer. He has a 22 rimfire, a 12 Ga. pump shotgun and a 308. He told me that he has never had a reason to buy any other guns. Some guys want a rifle for every concievable purpose. Its all in what you want to do with your resources. I know guys who spend so much on equipment that they have no money left for hunts they would like to go on. I have gone through all the phases. The Magnum craze, the habd cannon phase, the do it all with a shotgun phase and all the rest. Although I still like to try different guns, I could do it all with a 308 or 30-06.