Aliens are pure evil, they will kill off anyone, anytime anywhere.
Predators have a higher ethics presence, whether they were in the jungles of Central America, or Los Angeles, they never attacked an unarmed combatant
Well, I am not actually a fan, but I don’t call it exactly ethical to land on earth with superior weponry and the ability to cloak and take on earthlings - even Special Forces. IIRC, the predator in the first movie actually tried to instill terror, not just hunt.
In the sequel of AVSL we could discover if an alien that gestated inside a Sith Lord came out able to use the Force.