Well the problem I find with making another AVP movie isn't that it might turn out bad. They could really succeed if they have a good director, lots of resources, and most of all IMO, a script that have nothing to do with the pyramid stuff in AVP (meaning not a direct sequel). The thing is, the reason that most people watch sequels are due to the success of the previous movie. Since AVP wasn't much of a success, I'd say it'll be really bad to do a sequel for it. Though IMO, I would really want another AVP movie, a better one than the previous.
And about the third Predator movie being like what ressurection did to Alien, I slighty disagree. The thing is, after the third Alien movie, most of the mythos for the franchise have been established, so when ressurection came out, it couldn't possibly add more to it. That's why new add cr*ppy ideas like cloning, human-alien mix(Ripley) and the Newborns. The Predator franchise though, haven't been totally established yet. There are still many qeustions surrounding the series. These are things that books and comics like to add in (this depends on if you consider them canon or not). As long as they are not dointhing absurd like a half human, half predator, then it'll be fine.
We Endanger Species...
Preferably Yours