More realistic world generation

I wish Minecraft hade realistic generation. Like the desert having actual sand dunes instead of random mountains in the middle of nowhere.
 I want biomes to be massive instead of some biomes that are 100 blocks wide.

I want rivers to be more wide and long instead of a simple stream.

I want the plains to be more smooth instead of 100 block hills out of nowhere.

These are just some of many problems with the generation, I could go on and on but it ends here. Thank you