The issues:
Nonantags have no reason to do their jobs
Nonantags have no reason to board the escape shuttle
A suggestion how to overcome these issues and make things more interesting:
Crew and/or Personal Objectives for nonantags.
My examples aren't mindblowing, they're aiming at keeping it nice and simple.
Crew Objectives:
* Export 1000 [insert mineral].
* Export all the crates on the station.
* Keep the station as clean as possible.
* Keep the station as intact as possible (no hull breaches).
* Maximum research.
* Make a superhuman SE syringe/virus.
* Make x amount of mutated superplants.
* Have more than 90 % of the crew reach Centcom alive.
* etc. etc.
Personal Objectives:
* Don't harm anyone.
* Don't die even once.
* Never suffer asphyxia.
* Various tasks depending on your job, e.g. find Hulk when you're Geneticist, make an Adamantine Golem Rune when Scientist, clean 50 blood splats when Janitor etc...
PLUS The Round End Score
Depending on how objectives went plus the normal things (how blown up was the station, etc.) the round gets an overall score.
Yeah... I dunno, thinking is hard. But you get the point! I'm sure you guys can think of many awesome things.