I like Xenomorphs but i think that in some way their life cycle is not very effective, i mean, its easier to bred a¨puppy¨ xenomorph from an egg, and then it becames bigger and stronger, than a facehugger (Only if it could develop itself with no need of hosts, like insects). In the other hand, its the theory of the DNA pool and all that genetic weird thing. I don´t know who is stronger, i geuss technology doesn´t make a creature strong. Xenomorph weapons are it´s bodyparts, while a human without a gun is quite a sh!t.
I love Aliens 3 runner but i can´t understand why its supposed to be weak. (Try looking the Aliens 3 comic xenomorph, it´s not like the one of the movie, but it´s an awesome bipedal monster with a larger and sharper tail and it´s mouth full with fangs. The bird like foot makes a bettter look of the Xeno, very similar to Aliens: Resurrection Xenomorphs)
I like Predator´s chivalry code too.