Sorry to say, but it wasn't that scary, anything sufficiently humanoid just isn't compared to the xenomorphs. I think they might have been better off having a 'v' (miniseries) twist and having twins, one being more (or all) xenomorph.

I guess they partly wanted an homage to Alien Resurrection (the original human hybrid), the design of which I think was actually more effective in of horror. I see also an homage to The Fly, which is understandable, given the horror pedigree of the director, but felt a bit rushed, in a way.

It's a tough task, having to hit all the nostalgia buttons and keep a new story going with new ideas (and there were some excellent ones) and engaging characters, but I think a bit more attention could have been paid to character development, because they were great. Still a very good film, and a welcome return to form for the franchise!