RE: .308 or .30-06
Don't be fooled into thinking that a 30-06 can't be a tack-driver. .308s are the ones known for their accuracy, but "there aint no flies" on the 30-06. If you get a quality gun that will group well I can only see the advantage of a 30-06 being in the use of heavy bullets (180grains and up). From what I've read, for some reason, the 30-06 will handle these alittle better. .308 has surplus ammo available, your wallet will love that.
Find a gun that fits all your other requirements.....then see if its offered in .308 or 30-06, if your lucky the manufacturer will make the decision for you. If, not I'd lean towards the .308 for two reasons:
Cheaper ammo
Less recoil