Excellent post JB and much appreciated.
I agree with each of your points and since the OP stated he already has a 30-06 then your 200+ grain .30 caliber bullet recommendation is supremely valid and logical.
In my instance however, since I don't own any .30 caliber rifle, the diameter and weight difference between my beloved .277's and my .338 is sizable and useful.
That doesn't mean I'm not still hoping for a 9.3x62 in addition to my 338-06!