Re: Archenemy
Not all of the werewolves have to be Irish. I just thought it would add an interesting pov for them. The older ones (depending on how long lived they are) would see themselves as exiles while the youth would be about as content as young people are to be anywhere. Also if you had them as being somewhat in charge then you could have some good "flashback" type stories of the immigrants becoming the establishment.
I was unaware that the examples you gave were already part of those cultures. The only were other than wolf that I had heard of was werepanthers from Africa. Adding in werecrocodiles and other culturally based African weres could be a good way to show that Africa isn't a mono-culture.
Picking up an idea you brought up earlier I think Chicago would be a great city for a setting. It's a major city with an iconic skyline as well as suburban and ghetto areas. I've been to some locations on the lakefront that I could easily see weres using to let themselves go a bit wild. Also the world seems focused on New York most of the time. All of the major American news companies are there so there wouldn't be as much leeway should a human see a werewolf or get a video of a wererat. Unless you want the knowledge of weres to be widely known in which case media attention wouldn't matter.