M.
My friends have the last name Isla. When I first met them I thought it was Ees-la, but soon found out it was pronounced Is - La - exactly the way it is spelled. Now when I see the word, the first thing that comes to mind is Is -la, then EEs- la.
If you are looking to name a child eye la, which is a very beautiful name, why not spell it Ayela? My husband has a friend from college and that is how she spells it. Just a thought....