The front panel and the art throughout is amazing, you've got a really compelling pitch here and I love the repeated emphasis on “this is not a rescue mission.” So many Mothership crews might be tempted to be altruistic - this mean streak will set this adventure apart for any table. Bring a bastard to this one!
Where I feel the adventure could be improved is in the layout and hierarchy of information. The use of colour to differentiate text is a good starting point, but using only colour as opposed to alternate fonts/bold/italics in tandem flattens out the visual treatment and somewhat harms the readability in my view. I also feel the colour-coding could be given a consistency pass so a certain colour is only ever used in reference to specific story elements or mechanics.
So broad strokes: I think it could be pushed further but it's not much further to go. Print copies are already going to look and read nicely and the atmosphere/horror is fantastically conveyed already. Good stuff!