Before Prometheus, the AVP films were, for all intents and purposes, Alien prequels. I know, simply because of the quality of the films, a lot of people didn't view them that way (I didn't, but that's besides the point).
But what I was getting at was not so much chronology, but moreso portrayal of the creatures (in AVPR). If AVPR was a demonstration of what would happen should Aliens ever get on Earth, I'd say the characters in the Alien films overreacted a bit in their attempts to keep them off the planet (and in AVP, the same can be applied for the Preds who tried to keep them from reaching the surface). I would expect that, if Aliens were to infest Earth, we would have a scenario like the one the marines stumbled upon in Aliens, although on a much larger scale. We never really saw that in AVPR.