I like old school fae, the ones that are very "other", not so much the modern retelling where they're just humans with powers. I also like gods and godlike beings, especially when it's a behind the curtain's view of them.
If they do speak, it should be in words and ways that aren't readily understood - or which are misunderstood - by puny humans...
I remember in Babylon 5, when the unimaginably ancient Vorlons spoke, the writers would write out what they were saying, then pare it down to the absolute minimum, which was usually just one or two words or an enigmatic "Yes." They were communicating in as simple a way as they could to the tiny-brained humans/other sapients, but the meaning and nuances often flew right past them.