Well done Aurich! You did a very nice pulling off an atmosphere using the assets at your disposal.
I really like the color palate & the use of greens, blues & reds. The dark areas are balanced & well placed around the LCD screen. That should make the LCD pop. The star field works really well too. The bottom of the playfield is the best part, and you did a great job combining the motion sensor tracker with the head-on iconic image by HR Geiger. I think with everything put together & the lighting added, this is going to look outstanding as an overall package.
I guess the only thing I'm struggling with is that you created a mish mash of HR Gieger, photorealistic & comic book art. The Xeno in green at the top of the playfield is cool looking for sure, but clearly came from comic book art. It matches the art of the inserts well, along with the "cartoonish" flames on the dropship. I guess the top of the playfield has a more "cartoon" feel, and the bottom is more photorealistic images? I'm not saying that's a problem, but that was my first impression, and I'm wondering why you didn't go for one consistent look for the entire playfield.
With that said, I would only make a couple minor changes (and please don't take that the wrong way). I'd probably ditch the cartoon flames on the dropships for a more realistic propulsion effect, or remove it entirely. And the Nostromo really isn't getting it's due. It's a massive ship & it just doesn't come off that way at it's current scale, compared to the other ships. Does the dropship of the Nostromo really need to be represented in that area? It may be better represented with that removed & the Nostromo enlarged. I'm also a little sad the Marine transport ship Sulaco wasn't shown either, but perhaps it will show up elsewhere, like on the plastics.
I hope I offered some constructive criticism for you, as I don't like to throw stones at other people's hard work. It had to be hard to represent & combine elements from two different films into one cohesive playfield. Again, very well done!