It's all about absurdity. The Quarians having Israeli accents wouldn't be absurd. They could have Western African, Brazilian, Russian etc. as long as it didn't sound absurd or over the top.
Yes, I will admit, when I hear people say Jamaican accent, I go to the stereotype. And, I do apologize. BUT, since it is not like that, I will be dropping it. I'm sure it will sound fine, and I won't even be able to have the f**kin' character for a couple months after release anyways....Then Ill do more bitching about the character
Sorry.
EDIT: Protheans have more to do with the story than most races in the Mass Effect series. That's why people are getting hung up on it. They were suppose to be a grand civilization...then, when they do finally introduce a speaking Prothean, people think it's gonna speak like the Jamaicans from Predator 2.
There, now I'm done.