I'm not sure about the concept of using language well. I'd consider the use of language to be effective if it performs it's function. This function can be very varied, from the imparting of data to the communication of emotion.

I'm vary aware that much discussion on language use is not about helping to improve comprehension but is about putting down certain language forms used by certain social groups. This is most clear when discussing the, so called, taboo words but is also shown in many other examples of 'criticism' of english use.

I'm not familial with Love's Labours Lost but I wonder if Shakespeare was making a point about linguistic snobbery rather than being guilty of it?

I wholly agree with you that diversity is fun, it's also rich, enlivening and often frightening. I wish that people would face the fear of difference and embrace the excitement.