That's ethnic/genetic cleansing. How can nature perfect something through such horrific practice? There is something deeply wrong with the idea of "evolution" by dumping prototypes with the "bathwater" of unwanted genes.
Just because you don't like the process does NOT mean that isn't the way the world works. I suggest you spend a little time actually observing nature (either in the woods or via. cable nature channels). "Mother Nature" IS "red of fang and claw".
Also, your understanding of the evolutionary process is flawed--SUCCESSFUL mutations survive--only unsuccessful ones get "pruned". Is this a wasteful process?? Yes. Unfortunately, that IS the way it works.