OK. I am happy to go against the grain here. I have shot several 45/70's , Marlin, Ruger, and Handi. Anyone who tells you that a 405 gr slug at nearly 2000 fps in a handi has reasonable recoil is just blowing smoke up your kilt. The guys here are great, helpful and courteous, but there is still a group that is somewhat masochistic, and delights in pouring ever more powder into cases an stuffing heavier and heavier bullets on top. If you are into punishment, go for it.
I have been hunting deer here in Missouri for 44 years now, and I have killed many deer with the 45/70, my longest kill was 188 yards, one shot, DRT. The load was 33.5 gr of 4198 and a 322 gr HP Lyman 457122 bullet. The last deer I killed was the 10 pointer that I posted a picture here of in the "Handi success stories" last fall. It was taken at 92 yards with a 500 S&W, a 435 gr Lee cast bullet, and 21 gr of Blue Dot. The bullet passed cleanly through both shoulders and went 16" into the ground, and I recovered it, minimal deformation. It kicks about like a standard field load in a 20 ga, maybe a little less. That load in my gun produces a 1.5 " 5 shot group @ 75 yards, which is what my sight in distance is.
If you want a bigger bang, that is quite fine, but dont let anyone tell you that the 500 wont work just fine out to 150 yards, and is a great deer and hog gun. I will not argue that the 45/70 is not also excellent, and works better once you start stretching the yardage out, you can use lighter, faster bullets. No deer was ever killed deader by 3000 foot pounds than by 1000, just damaged more.
I have both, and I tend to take the 500 out more, it is lighter and shorter, and I think easier and cheaper to reload a bit. I can use either LR or magnum pistol primers, and I have loaded some cases 12-15 times and you cant tell them from new coming out of the tumbler.
I hunt mostly in heavy timber where there is a lot of bowhunters around, and if you can kill them with a bow, range is not much of an issue, you say you are here in Missouri also. If you are north of the river, maybe go long, but here in the south, the 500 works just fine. Get whatever strikes your fancy or comes up first or best deal, you will soon love either one.