Despite my longing (heh-heh) to include xenomorphs more in this story, this is their last appearance. (Or is it?) I have used the setting of Aliens
just so we have an Earth that has the capability of fighting the Guardians, without assuring either side of an immediate curb-stomp.
The story is going other directions from this point. I don't know if you are going to happy with that or disappointed, but we aren't going to be seeing the xenomorphs (or Predators, or the ancient alien astronauts) any further.