I guess the
Suzanne Vega song "
Luka" has gotten old enough that people don't think of it. I always think of it when I hear Luka-on-a-girl (because of
Vega's very feminine voice singing "My name is
Luka"). "
Luka" is a victim of child abuse in the song. Not a good association.
Anyway, I think it's not as good on a girl as
Micah is, but it would work okay. It's more like using
Noah or
Ezra on a girl IMO. Not my style, but doesn't feel bizarre or mannish like so many other man-names on women do.