What about they add a bit of variety to both side hmmmm, like The pred. in Predator 1 is some regular skilled hunter which is an expert in stealth kills; that's 1 clan, and the Preds in AvP are more advanced Predators that use mainly hand to hand combat and tech. to kill their prey; that's another clan. I'm just saying just add a bit more to each side so that people would like to know these creatures.
Heck, George Lucas is better than the Director of AvP. He started Star Wars in like the early 1970s and finished the whole story in 2005, that right there is 6 films in 35 years, but Predator started in 1987 and has only 2 films about them to this very day.
Look around each corner before you move because the chances are, you are not gonna make it.