I didn't know that GAY-a was common in English, I've only ever heard it pronounced GAH-ya. That's also the Italian pronunciation and they way it has been pronounced in most countries I have been to. It is quite common in Italy. Yes, the Greek pronunciation isn't very nice. Hmm I find it odd that people would say GAY-a because
Maya isn't MAY-a and
Kaia isn't KAY-a and these names are pretty well known. But it is interesting, thanks for your answer!