Bottom post of the previous page:
AI, because in addition to having loads of power and ability to change the round, you can do it differently in any given round. You can pick your own personality at the start and then work from there, you can put as much or as little effort in as you want (within reason, you've still gotta open doors) and sometimes other people (Captains uploading laws, borgs being just great) can make the round even better. Plus having your own borgs is like running a department where the staff actually typically listen to you and care about what you want them to do (kind of like I assume HOS is from that one time I played it).Medical Doctor is fun, you have a pretty chilled time most of the shift and then when you want to you can go and heal people. In high intensity crises it's really great: MD is the best job to do when there's a blob, for example. There's probably a bit too much standing around for most of the time but when you're in the mood for that it's the perfect job because there are normally a bunch of people in medbay to talk to.
Security Officer is just a good mix of these two: it's quite high stress and very busy but when you get it right and have a good team with you then there's nothing better. My favourite moments in this game have all been playing as a security officer, whether winning or losing. Mostly I don't think anything beats gearing up with a few other officers and murdering the hell out of a cult base full of constructs and cultists.