Human cloning is illegal. No one has ever performed it till now. I think that this practice will never be legalized. It is because of the fear inside us. We fear the calamities it may cause even before fruition. Opposition comes from all kinds of scientific community, religious institution and other communities. Majority of people who know even a little bit about cloning are against. For us, it is about doing things which are even beyond being called unnatural.
In my previous post Beyond Evolution: Biotechnological Revolution, I had written about how human cloning can take us to the next level. But before judging the gravity of it, we need to visualize what is going to happen in future.
In order to develop ourselves we only need to focus on one thing: the communication. And for effective communication we need effective voice. Our voice frequency ranges in 60 to 7000 Hz limit. This range should increase by incorporating desirable gene from various animals (ofcourse, it should be compatible). Over the period of time with advancement (possibly in next era maybe, but not before), we will require a grammar and an expansion in our vocabulary so that we may express our ideas as we will gradually understand complexities in universe (this is true, our English language for example is becoming a barrier in understanding few ideas of quantum mechanics). This is exactly the first thing we require, if we will start cloning a human. A larger sylvian fissure, a larger lung capacity and flexible vocal chord.
This is just one trait (or a part of trait). And there are hundred more to modify.