Just read on a french website that the scene showed at comic con where upgrade kicks fugitive's ass contain a shot where we see from upgrade's POV, and apparently he has thermal vision without his mask, just like in P2... I don't know if i like this, already found that weird in P2...
That was a mistake in P2, don't remember if in the extras they admit that. But in AVP-R and Predators and they the same vision from first movie.
The Upgrade having that would only give benefits if he is hunting on Earth, in other planets it might make things worse.
True. It makes me wonder if the way in which they "upgrade" themselves is dependent on the planet where they spend the most time. Like, they tweak themselves for their favorite hunting planets.
Considering how big the Upgrade have gotten I find it hard to believe his goal was to hunt on Earth, what's the challenge now? He is even more overpowered against humans than he already was before. If an "upgrade" was necessary so they could have chance against a much superior prey, that they really were getting their asses kicked for years and couldn't beat I would understand.
But becoming a 10 feet tall monster with better eyesight just so you can bitchslap humans easier just isn't what I would expect from a Predator.