.300 H&H followed by .30-06 if it were me having to decide in that catagory. Not that the .375 won't do everything either does, while still being able to work on bigger.

If I set up a 3 rifle battery, it would go something like .22LR or .22 Hornet for a light pot rifle. .375 H&H for a plains rifle. .450 class or even better .500-.577 double for in close with the big ones.

Just my take on it.