Thanks for your insight! Actually I only edit them through Manage World, so what you desrcibed is not the issue. I am aware that actively playing them will remove any NPC role related traits/jobs. So I make sure never to do that.
The sims I'm using are definitely suited for the roles, because they have all had them before. It's just after editing them (through manage worlds) that they lose their roles. I now have like 8 homeless sims that used to be librarians, all suited for the job, but the game keeps generating new ones.
It also keeps making new retail workers, even though I've imported some retail workers from other save files through the gallery. But the retail workers do keep their roles after I have edited them in CAS, so that's not a big issue.
