If you have a .270win, and 30-06 and are looking for something new, I'd either go smaller, or bigger, 7mm Rem.Mag. wouldn't be a choice/option IMO, nothing wrong with it, just too close to the others.

So I'd look at something .243 or smaller and/or .300WSM/win.mag and bigger...

A .243 is pretty versatile from varmints to mule deer, probably ideal antelope round.
and a .300win.mag is a great starting point for elk and larger animals...course with a .338 or larger you can very effectiviely hunt anything big/dangerous in North America if not the world...so maybe consider one of the .338's or a .375H&H if thinking bigger.