Create Biomes with Coordinates

This seems like a rather simple idea to create any kind or any number of biomes within your world without the use of any mods. Hopefully all platforms can take advantage of it.

Would if Majong could implement a command within Minecraft to create your own biomes available simply by using coordinates just like the block fill command.

Simply select biomes, then seed type or biome, and then the coordinates of the boundaries. It seems rather simple.

Now the trick is there is, when it comes to filling blocks, there is a limit to how much can be altered at once as of now. So I imagine the same will be for the biomes. But even as a beta it would be great to practice with. And hopefully would be improved upon in later updates.