When you look at a 44 magnum compared to a 12 gauge slug you would not think they would be that effective. After taking a deer with a 44 Magnum I am impressed. I use a lever action Rossi with an octagon 26 inch barrel with open sights and love it
I used a 454 casul for deer and to be honest it was a complete waste of energy, I hit the vitals, the bullet passed through and blew the opposite leg off (held on by just a very little bit of hide and tendon) and went into the ground. Those guns are fun ( I own a 454 and a 500) but are way to big for deer hunting IMHO.
So, I guess to answer the question, there are a lot of options out there, each one is somebody's darling. Pick one.
Seems to me, one should get something that they want to use, and use it to the point of mastering it. Get some training. Get lots of dry-fire and live practice. Be able to hit targets as effectively as walking.
The "very best" rifle/ammo combo can produce spectacular misses if the shooter does not do his/her part at least adequately.
That's all I ever used until last year when I went out with a 300 BLK Ar pistol. I used an old Thompson Center for many yrs before upgrading to the CVA Optima about 6 yrs ago.
Pick something that excites you and feels good in your hands and go with it. If you like AR's pick one. If you reload you can pick something more rare. If you like older gun take one hunting like it was meant to. I bought a 1969 Marlin 35 Rem and started handloading for it. Shoots little bitty groups and kills deer like the Hammer of Thor. Have fun with whatever you choose.