I actually like the designs of the Jungle, Lost and the AvP Predators. In other words, I like both the used and worn appearance of the Predators of the first two films, and I also like the newer look of the AvP Predators quite equally. Personally, I chalk this up to different clans having different aesthetics and perhaps even levels of technology. Some of the old EU material did mention that some clans had technological achievements which were unique to their own respective clans-- so I see this as reflecting on their weapons, armor and by an even greater and noticeable extension, even their vessels.