To a certain extent use of the characters is about willingness of the writers to add story elements for them. I thought making Chekov chief engineer made about as much sense as promoting Chapel to chief engineer. They just wanted to include the character more and could not think of anything to do at navigationnin a movie context. Beyond used him far more effectively IMO.Depends on how realistic TPTB depict the job of a nurse. In large clincs, in hospitals, and in the military nurses are the ones running the show and their jobs are very wide ranging, the doctors have fairly narrow roles to play.
I hope they keep it minimalist and keep the door open:
Kirk "Where's Chekov?"
Spock "Still recovering from the encounter with the space hippies, Captain."
Kirk "Space herpes? I had that once on Rigel VII. It burns like a..."
Rand "Space HIPPIES, Captain..."
Kirk "That will be all, Yeoman."