Problem is that, that's still high. The biome is usually as large as a jungle biome and the benefits of the biome make it even more reason for it to be rarer (although this is not my reason for wanting this config option). The biome itself has a mass amount of color (as it should) but because of that; If it's so close to normal biome rarity it ruins that majesty of nature with its in your face color scheme. I less want the rarity for balance reasons, more for aesthetic reasons. I personally think I find them waaay too often and It ruins the flow of the world for me, I'd like to drop it's weight down to 2 so it's harder to find but it's never too far out of reach and like I said, the biome is usually huge so you don't have to be worried about this choking the resources for the mod.