When we joined a few years ago the waterfall areas were gone within the first 30 minutes, it was hard to find an area for example that has the luscious green vs the more bleek cold that we have now. It's fine, we've build with it and love it.
But we're a few years down the road and I'd love to perhaps change some chunks here and there or an area to a different type. Maybe more cold so perhaps polar bears can spawn there. Or perhaps turn it into a summer theme finally with some luscious green with flowers etc. I know it won't magically put snow blocks down or change it to flowers everywhere, but the way the textures look will be colder or warmer, and the weather would be rain or if we change to a desert, no rain- or perhaps all snow instead of having chunks that for some reason only have rain despite that it's a snow all around it.
If we could perhaps use /gem to pay for a biome change, that would be cool.