If you invented a totally new CT career, or one added in later editions such as Bounty Hunters, Entertainers or Law Enforcement, then it would make sense to include a page to cover a basic career.
There's also scope for Citizens of the Imperium 2: Eclectic Boogaloo with another 12 careers. You could likely backfill most from TNE (which still has the largest list) or Mongoose. Psion and Prisoner might be good inclusions; although CT locks you into one career, you could go with something like converting a failed survival roll into jail terms, with adventuring starting on release. Psion as a career is present in the Zhodani Alien book, I guess.
Here's a list of careers that have appeared as options post-CT:
Law Enforcement, Athlete, Attorney, Bounty Hunter, Civil Engineer, Civil Pilot, Computer Programmer, Construction worker, Entertainer, Farmer, Journalist, Manager, Martial Artist, Mechanic, Mercenary, Merchant Marine, Prisoner, Rebel, Truther, Believer, Psion. (I equate Mongoose's Wanderer to CT Other, but you could make Wanderer a career, sure.)
Skyport Authority from JTAS 20 only gave us advanced character generation IIRC, so that's a possible one too.
Tidying it up, and using some of the ways Mongoose chose to rework the TNE list and throwing in a couple of my own, here's a suggested 12:
Law Enforcement, Mercenary, Bounty Hunter, Citizen, Colonist, Journalist, Entertainer, Attorney, Believer, Spacer, Technician, Hacker.
I would combine workers and managers into Citizens, with Managerial being the "officer" stream. Colonists would be a different life experience than settled Citizens. That's where you find your animal skills and tough frontiersfolk. Spacer is a career that I think should always have been there. Not the merchant princes or the military or the explorers or the miners, but the people that live and work in orbit and operate the in-system craft. Maybe also including low G dome dwellers.
Not a final list, no real rules in mind. Feel free to pick it to shreds.