Recently a user on Mastodon had a thought about Lt. Ortegas. She is clearly part of the Engineering/Operations division, which is abnormal given the triad of gold that normally sat on the bridge during Kirk's five year mission.
So I began to dig. José Tyler wore Command gold with an engineering insignia. Detmer wears bronze on the Discovery, which continued into the 32nd century. Gary Mitchell wore the darker operations color with a Sciences insignia. I think this suggests Helm can be a multidisciplinary position, though it is typically staffed by a young Command officer. The Command division tends to be more administrative or dedicated to control functions, but we also have Vice Admiral Toddman who wore Security yellow and Earth Starfleet's Maxwell Forrest who also did not wear Command colors.
Continuing forward the exceptions to the rule become less frequent. Lt. Leslie manned the helm as an Operations officer several times under Kirk and Demora Sulu wore Operations gold as the Enterprise-B's helm officer.
I have not dug terribly further, but outside of the 23rd century, the only notable helm officer not wearing command colors is Hector Illario.
Are there any other notable helm officers who don't wear Command colors?