I'll give it a 7.5.
Even though I don't know too much about these two races, but what I learned by reading what yall posted, also, seeing the mistakes that yall pointed out in the movies. I have to say, it's really good.
The reason why I said it's really good, is because, look at that one scene. The Yautja did a really cool trick as he super jumped and impaled his spear into the Queen's head. You won't see that trick in the first two moves, so you have to put a plus on that. Also, look how the mandibles moved. They all seem to move independently, like a pair of human lips. So what about their size not matching the first two predators. It gives off a question that, they are part of a whole other clan, so I heard that they live like Tribal people or the like. You can't just say, they are disgraceful way to show a predator, for it is like saying, that all people on the earth should be White, or Black, or any other color, OR, they should only be fit. not too skinny, too fat, nor too bulky. You got to add some character to a race, right?
I know there are multiple mistakes in AVP, like the Yautja could've skinned those guards that were outside, gaurding the tunnel, but I assume that Anderson, didn't want to scare the children, so he only had them hang them up as the way they are, and THUS, making it a PG-13 movie.
Now to the Xenomorphs. From what I saw from Aliens, compare to the movie AVP. What they done, really made them come to life in MY oppinion, but also, my knowledge is limited about their movement, styles and behaviors.
In the moment of action remember the value of Silence and Order.
-Phormia of Athens