When in doubt go for E it's probably the sound you're looking for.
Greek is not an easy language for my north american eyes to cheat their way through. It seems that there are too many consonants and strings of vowel-like symbols mixed in with other shapes that make me think more of frat boy belches and "Revenge of the Nerds" than of a living language. This means that my ability to osmose the language is considerably slowed. I read more painfully slow than a 4 year old. As I stumble over words on the written materials that surround me, I feel for the people who must endure the abuse that I daily give this language.