I suppose it would be cheating to count characters who were in both "The Cage" and "The Menagerie."
Let's see, searching through my old pencil-and-paper list of Enterprise
crew, and double-checking with Memory Alpha...
- Lt. DePaul (Sean Kenney): navigator/helmsman, "Arena," "A Taste of Armageddon"
- Lt. Hansen (Hagan Beggs): helmsman, "Court-martial," "The Menagerie"
- Dr. M'Benga (Booker Bradshaw): doctor, "A Private Little War," "That Which Survives"
- Lt. O'Neil (Sean Morgan): landing party member, "Return of the Archons;" transporter operator, "The Tholian Web"
- Lt. Palmer (Elizabeth Rogers): communications, "The Doomsday Machine," "The Way to Eden"
- Lt. Kevin Riley (Bruce Hyde): navigator/engineer, "The Naked Time," "The Conscience of the King"
- Lt. Johnson -- David L. Ross only played a character by this name in "Day of the Dove," but was credited as Galloway in "Turnabout Intruder." Since Galloway died a season earlier, and since Ross's character was unnnamed in TI, I tend to assume this was Johnson's second appearance.
- Angela Martine -- Barbara Baldavin was called "Angela" in "Balance of Terror" and "Shore Leave," but was called "Lisa" in "Turnabout Intruder." Still, some sources credit her as Martine in that episode. (She also appeared in deleted scenes from "Space Seed.")
- Osborne (unknown performer) -- A security officer identified by name in "A Taste of Armageddon" and "The Devil in the Dark." The same extra appeared in "Return of the Archons" but was not named, so it's unclear whether he was Osborne, though Memory Alpha assumes he was.