I wouldn't mind a new cast, too. But in the end I feel they'll go with the most marketable way, which is bringing back the characters (Which is a reason you go to see sequels, right. What if you saw The Empire Strikes Back and non of the characters from Star Wars were there?). Since everyone is older, I don't know how well it'd go. (I'd actually like to see them just leave the series alone)
But as someone who aspires to be a screenwriter, I don't think it's very good writing to just kill off two characters at the beginning of the film. I get that Alien 3 is supposed to be a much darker film. But that doesn't excuse bad writing, that'd be like saying bad writing is okay just because a film is a kid's movie.
Killing off the characters at the beginning of the film is bad writing, because it's just a way to conveniently leave Ripley alone. Like I said, I wouldn't mind if Hicks (and newt?) died in Alien 3, it isn't a problem that they died in the film. The problem is they just die; we don't even get to see them die.
How is this not lazy writing?