I don't really understand Predator fan logic.They are a fan because they can relate, because they use technology, and they are like us.
In a monster, you don't want that. You want something that is completely different, something that you don't want to root for, something that doesn't need weapons because it's just that tough. And definately not something that is very similar to humans.
The Alien is very different. They are all those things. You don't relate to them, making them the complete and utter bad-guy. You don't know much about them, they don't rely on anything but themselves.
The Predator is something that is like a twisted human. It's a monser people. Not some kind of X-Man. Not some kind of cool good-guy freak.