id love an expanded story about a defective alien "protecting" a human. At the same time I totally get why someone would hate the idea.
You can always pull an Alien 3 by having the main character infected with a queen alien to justify it being protective.
The next step is make the queen a stillbirth thus 'defective' and decaying within' the person unbeknownst to the alien. You can add some nutty psychosexual context to all this while the MC is slowly losing his/her mind due to isolation. The crux of the story is the character searching for ways to remove said chestburster knowing it could draw the ire of her guardian angel, while at the same time the planet they're on is filled to the brim with hostile life and the alien is perfectly adapted to wrecking house if need be, forcing this kind of fragile dichotomy ultimately.
You could use the thyroid condition Ann Crispin came up with to explain Purvis' delayed bursting in the Resurrection novel.
Or the leprosy angle from the older comics.
I finally read this and burned through it in one sitting, I liked it quite a bit. The opening with the destruction and chaos gave me 'Dead Space' vibes (specifically the prequel comic and Dead Space: Extraction for the first game, and the chaos early in Dead Space 2 on Titan Station), and the constant momentum with very little breathing room was engaging. I liked the artwork for the most part - it was consistently dark and ominous, but clear enough to know what was going on.
The "mom Alien", though.... I think I'd have liked it more if it was handled more ambiguously. Like, the idea gets talked about and one of the characters basically says "that's stupid, and you're stupid for theorizing it", which was a step in the right direction. There was the bit where the Alien tackles Maxon and doesn't quite get a chance to harm him before the swinging arm thing knocks it away, and that was the kind of ambiguity I liked.
And then the Alien fights the Queen at the end and I went "lolwut".
All in all I liked it more than Dead Orbit or any of F&S/L&D, and the second half of Defiance.