You raise some interesting points Scorpio.
I mean, they are already ridiculously humanoid for an alien species. Look at their pectorals, their six (sometimes eight) packs, their biceps, their five fingered hands etc and their incredibly anatomically modern human shape, even Neanderthals had more differences compared to us when it come to body shape (not counting the heads and feet for obvious reasons.) Plus Predators have a chin, humans are the only hominid, the only primate to have a chin! Again, Neanderthals lacked one, Erectus lacked one, Heidelbergensis lacked one, Floresiensis lacked one etc but this totally ALIEN creature has a chin whereas some of our closest extinct relatives lacked one and were more ape like.
I wouldn't be surprised if Predators have a similar skeletal structure to us.
So, good point on the breasts actually being more for sexual selection than actually mammalian traits. I never considered the Peacock feathers analogy. And true, human breasts do seem as if they are sexually selected.
I am not against female Predators having breasts (I liked Steve Perry's take on them, larger, stronger and more aggressive females with breasts), I don't want them there for the sake of making them "sexy", but for the sake of going "look, a female!" If their males are ludicrously similar to us in so many ways, might as well make the females identifiable as such.
I never understood the "it makes them too human" argument, because they're already a very human-like species. The only differences are the blood, the insides (multiple hearts according to the new books), their longevity, the vision (even their eyes look similar to ours whereas if you look at a goat or a cat's eye, they're quite different.), five fingered hands, walk on their heels rather than digitigrade etc. Even their dreads are positioned in ways similar to human hair, plus they have "facial dreads" almost like growing facial hair. They have very expressive faces just like we do, they're social like we are, they hunt for sport like we do and collect trophies like us... they build cities and pyramids like us... they live in tribes and have various different cultures like we... I could go on forever.
The only things I can see as being truly alien about them are their languages due to the shape of their mouths, they'd have incomprehensible and inimitable languages. And their culture overall could be very alien, plus they have huge brains in their heads (and their heads are big, so a big brain to body ratio) means they'd have more complex brains leading to a more intelligent race than us who would also think very differently as a whole. Trying to cognitively anthropomorphize them by assuming "they share our morals" would be a mistake. But physically? Man, you don't get more anthropomorphic than that, guys!
It'd make for interesting discussions about convergent evolution. It's happened here on Earth (even though everything here's related), so evolutionary pressures and similar paths could've pushed the Predator species towards looking very much like us.
