If you have your heart set on a big bore then I vote the 45-70, factory remington loads have less recoil than my 307 win. If your concerned about recoil then I say 30-30. My first lever gun was a 336 in 35 rem surpised me how hard that gun kicked, may have just been the load and the inexperience of the shooter at that point though. I think your right on with the lever gun/open sights in the brush country, I shoot a m94 in 307 with an XS system ghost ring and a m7600 in 35 Whelen with a Williams peep mounted on the receiver as my two brush guns. I would also look at the 760/7600 pumps that will give a wide variety of chamberings, you can probably find a used one in a pawn shop at a resaonable price. Just some food for thought.