well, interesting idea but...yeah its already in the xenos house.
regrowing arm in the novel of the first movie, after an airlock door cut it up from the creature.
and also used in the avp extinction game.
i think prosthetics for the preds are much cooler, because they have futuristic technics and stuff.
the predator is strong enough an he has to got some points of weakness too because otherwise it would be unbeleavable and boring.
i mean whats next ? wings ? magical powers ? hypnosis ?
the pred shouldn't be a superhero
and neither does the alien