Easier way to update

So I've been running a realms world for a while now, and I'd REALLY like to explore the new cave and mountain biomes. Unfortunately, doing so at this point will probably require that I explore thousands of blocks out, and when I get there the chunk boarders will probably be really jarring. I would like there to be a better way to update your world to new versions. One that doesn't include jarring chunk boarders. I get that minor chunk errors are unavoidable, especially between versions, but if there was a way to more seamlessly have a transition between chunks that would be great. I think that, for this update at least, a way to update just cave biomes and not the rest of your world would also be nice. I get that this is a lot to ask, especially since it requires so much consideration and so many different variables to ensure that the fabric of the minecraft universe doesn't tear into pieces, but this is really the only problem I have with the game right now. Because this game is infdev, your world will eventually become obsolete, and many of the things people in new worlds could experience and enjoy easily, your five year old survival world which you've poured hours into becomes outdated, and just getting to the new things is nearly impossible. And even if you get there the chunk errors could break your sense of immersion. If you could somehow work java miracles and make this happen, I think a lot of people would appreciate it.