Can you edit service sims without playing them.

You can either go to Manage Worlds and tinker with the world Sims from the Sims icon at the top, or use cas.fulleditmode on. If you do Manage Worlds, the played families you have are in the left tab, the unplayed/random townies are in the right tab, and the game can only keep about 200 of them before purging. So look through this tab and find the service Sims you want and edit them in CAS from there. Be sure to uncheck "played" when you return from CAS, as the game will default any Sims you edit into the "played families" category, and this can sometimes mess with service Sims.

If you're using the cheats, you can Shift+Click any Sim and enter CAS directly from wherever you are in game and make edits from there. I use this method a lot since it's quicker.