I love my 30-06, got a 270 a few years ago, wow, that one really shoots good, and kills like lightning! My 243 is a joy to shoot and quite accurate with nearly any load. Of course, my all time favorite 7mm, currently have a Rem.mag, and a 7x57, both straight shooters, haven't hunted with them yet, but either one will work for WA state big-game.
I'm starting to forget the recoil of the 338Win mag that was sold several years back, thinkin' a 338-06 would be just right! No desire to have another 416, recoil was all that I remember about shooting that rifle!
Why have bigger calibers? I dunno, fun, curiosity, "collecting". Why not?