Seriously; don't worry about the snakes, they'll all be denned up sleeping by Rifle season. Bow season is only gonna be dangerous if you are hunting near a river as they'll be heading home for winter.
And 308 is about right IMO... and nope, I don't have one ( perturbs me when folks pump up a caliber because they own one... means more when they give it a thumbs up just because it's good)
Fair enough, that being said we like to go on a lot of walks so it might not be the worst investment in the world.
I looked at the drop on 308 and 270 and just didn't see much difference at all up to 400m. 6.5x55 does quite a bit better and 7mm Rem Mag definitely is a 400m calibre with great ballistics but ultimately not enough there to convince me to drop a lot of money on an expensive calibre.