I've been shooting a .243 and .30-06 for many years. If you exclude brown bears, the .30-06 is adequate for all North American game. While the .270 and .280 can take an elk, most of the experts will tell you a .30 cal is preferred for elk sized game. Have plenty of experience with the 06, I would highly recommend it.

This spring I bought a .300 WSM (Stainless Model 700). The new R3 recoil pad makes it a pleasure to shoot. It kicks harder than the .30-06, but not as hard as the 12 gauge with 3.5 inch mags. The .300 WSM has the best of both worlds. The same .30 cal bullet as a .30-06 but with better trajectory than the 7mm mag and more power than both the .30-06 and the 7mm mag.