I would go with the 25-06 rem with 115 to 120 grain bullets.This a very good deer/black bear, varmit combo.I have been shooting deer with one for 11 years and have never lost a deer I have shot with it.
As for the 243 and 25-06 being to close together,I have had a 243 and IMHO it can't hold a candle to the 25-06.
It is plenty of gun for deer out to 350-400 yds and then some and antelope as far as you can shoot them.
BBJ