I'd say combine the old sound with a new sound. Utilize some remastered tracks from James Horner and Jerry Goldsmith's tracks from
Alien and
Aliens (in particular, a revamped
Ripley's Rescue,
Newt's Rescue, perhaps? And
Bishop's Countdown. And
Corridor, from
Alien). Could be a good idea to bring back Elliot Goldenthal as well, or remaster some of his
Alien3 soundtracks.
The new sound should be Richard James from
Aphex Twin (someone who greatly inspired Die Antwoord and Neill Blomkamp).
Check out the tracks "Mould," "Tree," and "Grass," - as well as "Icct Hedral - Philip Glass Orchestration" to get an idea of what you're dealing with.