Welcome aboard Tim!!!
As Bang_Ow said, ya got to have all of em, just one at a time!!! Figurin out the order to get em is the hard part!! The 30-30 as well as the 45-70, 223 and Hornet are all near the top of the most popular barrels to have list, and like Bang_Ow also said, you can't have too many 45-70s!!!
And when ya get all the factory offerings you want, there's always custom chamberings from your favorite gunsmith, a 45-120 BC, 405 Winchester, 338-06 A-Square, 35 Remington, 280 Improved, to name a few....to give you a taste of the possibilities!!
Tim