Welcome to the forum Red.
I noticed you were talking about high BC bullets but had a very large gap between the .30 cal and 6.5mm, and didn't mention the 7mm... Berger recently released a 195 Hybrid that has a .754 G1 BC and a .387 G7 BC.
7mm 195gr Extreme Outer Limits Elite Hunter | Berger Bullets
I see 6 mm and 6.5mm rifles winning 1,000 yard/meter matches to exclusion of almost everything else. It seems folks with 6.5 mm barrels are replacing them with 6 mm barrels. A 6 mm bullet just doesn't have the energy to hunt deer past 400 or at the very most 500 yards. I wouldn't go past 250 or 300. With a 6.5 I might shoot a deer at 400 on a still day. I know my long range shooting days were over in when I turned 60 and my hands started to shake from having Polio in 1948. I was always at best a 450/500 yard shooter. But I could kill a coyote on the run most of the time with a 6mm Remington out to 350.
The stuff we have today would have stretched that out to 800 yards or more for me.
To me a long range rifle is of reasonable weight and recoil. The less the recoil the more shots you'll shoot to practice. The lighter the rifle the more miles you will hunt with it in a day.
The 6.5x55 Swed and 6.5 Creedmore are moving at speeds someone might learn to dope the wind with of the rack ammo at long range well enough to make an ethical shot at a deer at 6 to 8 hundred yards before they needed a new barrel. I don't think many other guns can fill that bill.
You need a gun to fit the job. It must kill the game. You have to carry it, no bearers, and if you develop a flinch practicing long range hunting it may ruing you for good. I've seen more than one that couldn't get over a flinch. I don't know what a 6.5 won't kill with the right bullet. Ammo is available world round for the 6.5x55 Swede. The 6.5 Creedmoor seems to have met it design goal of a reasonably priced rifle that can win long range matches with store bought ammo. The commercial ammo for hunting shoot almost as well as the match ammo.
Show me two other guns you can set up for under $1,500 bucks including a good scope and have change and use of the shelf ammo for deer at 800 yards almost every time.
If someone is going to learn to hunt at 600 to 1,000 yards they have a lot of walking and shooting to do it. It really needs to be done shooting live game such as coyotes, Jack Rabbits and such. You need to learn to judge the drop, lead and dope the wind on the fly out to at least 300 yards. You can shorten the range by using 22 shorts that drop a foot in the first 100 yards. Shorts on running Jack Rabbits worked for me. The dust works as a tracer if you shoot with both eyes open.