But Cpt. Lundgren, your forgetting several other types of medical personnel
Enlisted/NCO:
Nursing Assistant (more of an admin. type job)
Medical Technician
Lab Technician
Paramedic
and the lowly Orderly.
Officers:
Medical Officer (the Doctors of Starfleet)
Medical Specialist
Nurse (again dealing with more of the admin. portion of the job)
The CMO, in my mind is some one who has taken extra steps in their training. Being able to not only deal with a variety of medical challenges (if a Specialist wants to go for CMO they will need to branch out so to speak) but also the administrating of a large force of other specialists, and the facility they work in. On Starships they'll need to be able to cover for any lack of specialists at least for a time, Starbases and Dedicated Medical ships not as much, as there should be full specialists coverage. Also they need to have the rank so as to command the Department they have.
Here's a (not complete) list of possible medical positions that would need to be filled:
Officers:
Chief Medical Officer
Senior Medical Officer (basically just a higher ranking Medical Officer)
Medical Officer (or Medical Generalist, when compared to the next entry)
Medical Specialists: Here's a list of some: Anesthesiologist (anesthetic), Cardiologist (heart), Dermatologist (skin disorder), Epidemiologist (epidemic disease), Forensic/Coroner (cause of death), Gynecologist (female reproductive), Neurologist (nervous system), Neuro-Psychologist (brain function relation), Obstetrician (child birth), Ophthalmologist (eye), Orthopedic Surgeon (skeletal and joints), Otorhinolaryngologist (ear, nose, and throat), Oral Surgeon/Dentist (teeth and mouth), Pediatrician (infant and child), Pharmacologist (medications), Cosmetic Surgeon (appearance), Psychiatrist (mental and emotional disorders), Radiologist (medical radiation use), Sports Medicine (muscle and soft tissue), Thoracologist (torso, heart, and lungs), Trauma Surgeon (emergency damages), Urologist (urinary tract and urogenital system), Vascular Surgeon (artery and veins), Virologist (viruses and viral disease), Xeno / Exo (add to any of the above specialties) (man does my spell checker hate me right now)
Head Nurse
Nurse
Enlisted:
Medical Technician
Lab Technician
Corpsman/Paramedic
Orderly
Special Description:
Intern (Normally only at a Star Base) I also refer to this as a Medical Midshipman. The equivalent of the Cadet Cruise for medical personnel.
Resident Physician (First Year Position for a Graduated Medical Officer)
Phoenix...
"I'm not saying there should be capital punishment for stupidity,
but maybe we should just remove all the safety lables and let nature take it's course"
"A Place For Everything & Nothing In It's Place"