Rocky balboa had nothing to do with the other Rocky movies, it has zero replay value
What the hell are you talking about?
He returned home to the place where he was born. It comes full circle. He started with nothing in the first movie, reached a peak around Rocky III or IV, started to lose it in Rocky V, and is now aged and living his most modestly ever, now without Adrian, just like how he started. If you can't see the journey of his character than you obviously don't understand it.