I don't really want another unless they keep it serious and grounded. I mean, yeah the first film is campy at the start, but once the Predator enters the scene the movie becomes quite serious and tense. And it's that aspect that I think is missing from the later films. It's a bit like how the Terminator franchise is missing the horror aspect that the first had.
Apart from that, the usual good writing, story etc would be great. It's kinda tiresome to be disappointed with this franchise at this point. I just wish they'd do it properly, ffs.