Granted, the first film screwed up some things, but it was far more respectful of both franchises (like not deliberately f***ing with canon). In addition, the Predators in the first film had a valid, believable in-universe explanation for their skill sets, weapons and armor. In AVP:R, the Aliens just happen to be stupid, relatively short, and physically weak for no apparent reason. And Wolf isn't allowed to get acid burns, evidently.
AVP:R was good, albeit flawed. It did a lot of things right, but it got some major things wrong. And considering the Strause Bros. have stated they're big fans of both franchises and have a great deal of knoweldge about previous installments, you would think the film would've turned out much better than it did. It had "Predator Fanboy Film" written all over it. Personally, if Fox does do AVP3, I'm hoping "The Brothers Strause" get the boot.