It would make a great companion to your 45 colt handguns.
I don't know much about rossi firearms other than that I want a circuit judge. On that note, have you looked at the circuit judge? Basically they took the "judge" handgun platform, added a stock and a longer barrel, and called it the circuit judge. It shoots .410 2.5" and 3" shotshells and 45 colt as well.
Single action/double action .410 shotgun and 45 colt in a rifle platform.
http://www.rossiusa.com/product-deta...adcrumbseries=
Marlin 1894 Cowboy is also chambered in .45 colt. They have a long history of making lever actions, and we actually own a couple of them. Worth checking out.
As far as hunting, I don't know how viable 45 colt would be against a deer at 100 yards. Shot placement would have to be perfect, or else an injured animal is going to run too far away to find. You would get a lot more punch with a .44 magnum or something. I would feel much better about .44 magnum for hunting or defense against whatever might need to be shot.