I just registered. I'm a fairly recent convert to the OC. I saw the "bane" thread and was interested in what it brought up. So I thought I would say hi to all my Byzantine Catholic / Orthodox brothers and sisters (and to any Western Rite Orthodox or Latin Rite Catholics who hang out here) and then make a couple comments.
I haven't been around long enough to know what makes a parish survive or not do so well, so I won't pretend to have the answer. I will say that I think that people in the USA are hungry for mystery and mysticism, which have been practically banished from our culture. So you'd think a lot of people would be attracted to the Eastern Catholic Churches or the OC. And of course, a good number of people are, but in general, the public picture of Christianity in the US is utterly unlike what we have in the "East." I mean, utterly unlike. I think countless millions of people don't even walk through the door...because they think they have to go to India or Japan for something with a little mystery to it.
And I wouldn't be surprised if the same happened even within Eastern Churches. Children grow up with the external forms and even good catechesis often can't keep up to their spiritual potential. Eventually the Church feels like a charade, they detach from it emotionally, and later on they leave.
Maybe in some parishes language is an issue, but I have heard this sort of thing described even in English-language OC parishes. So I don't know.