There is no ONE-SIZE-FITS-ALL perfect all deer rifle.
au contraire mon frère
there is, and here it is...
it actually fits everyone, 15 big game in 5 seasons (well 14 big game and a wolf which I'm counting), a Dad and 2 kids, 6 kills by the kids, 9 by the Dad, 10 yards to 420 yards, all three of us have dial ups on deer 300/355/420, deer kills have been 70-420 yards, we've got a few black bears 10-55 yards, 6.5 ft/lbs recoil energy means it still 'fits all' in terms of shootability, 6.5 Grendel, Hornady 123gr Eld-m factory ammo
3' feet of ultimate one size fits all deer rifle right there, you can keep your pack on and shorten the lop with the press of a button for still hunting, or sit down and wait leaving pack on as a back rest, 21st century options only will work for this discussion imo, if your rig can't fit everyone(recoil included) then it's not the ultimate...just might be the ultimate 'for you, or some of the people'
another thing that makes this 'ultimate'...everything off the shelf, including the ammo, sub-moa, zero fat, 1700 fps comes at 500 yards, a deer dropped at 420 was 1800 fps impact, watch it all in the scope, oh and illuminated reticle for low light and bush, plus intuitive for anyone to place at crunch time, ultimate ultimate ultimate