I like the .30 calibers. As for a romantic round (?) I'd choose the 30-40 Krag.
I like a rifle/cartridge combo that will push a 180gr .30 cal at somewhere around 2400fps on up. Not a big magnum fan so I suppose anything from .300 Savage up to 30-06 would be fine for my hunting.
My number one hunting rifle is my sporterized single shot 98 Mauser chambered for 31-40 AI which is, ballistically, more or less a 30-06 that shoots a .315 diam bullet.
If I was only allowed one rifle for hunting it would be an older Savage Mod 99 in .300 Sav.