Marvel also has their Max line that they could theoretically use. That's something that could vary project to project, with some more mainstream stuff releasing under the general Marvel banner and more, shall we say, explicit, material under the Max label. Marvel doesn't shy away from telling stories littered with sex and profanity and grisly violence with some of their own characters under this banner, so I don't see why they would be totally opposed to doing that with Alien and Predator from time to time.
They certainly have options. Whatever the case winds up being, the only thing we really can do is wait for more news and hope for some cool stuff.