All the other avatars were born in the city (Brooklyn, the Bronx, Staten Island) or have lived there a while (Queens) and don't lose their knowledge of themselves.

That's neat and I see the structural relevance. Does he ever recover his past, or he does just move forward as the avatar of Manhattan with whatever other character traits he turns out to develop or display along the way?

(There are plenty of Black Jews and I don't see a lot of them anchoring novels; I would have enjoyed that.)