Max Ray's appearance was based on that of the title character of "Magnum, P.I. (1980)." He also resembles Olympic gold-medalist swimmer Mark Spitz.
Had the series continued, the writers considered adding another Centurion: Ace's space specialist brother, Vic.
According to Kenner's employees and archives, the show was originally considered to be set in a dystopian future. One idea, which would have been titled "Ring of Fire", involved the title Pacific Ocean area's volcanoes all erupting and turning the US up to the Rocky Mountains into a stone wasteland, and Dr. Sevarodd Rom using "regenics" genetic engineering to merge with the supercomputer brain Syntax after a plane crash then basing himself there to try to destroy all life. The opposing "tech team" trio, from the army, navy, and air force, had abilities enhanced by regenics' exo-skeletal implants. The other concept, "United We Stand...", had a villain named Half Mad trying to steal the military supercomputer Syntax to create a world to rule, by sabotaging the world powers' computer banks to start World War Three. The 21st Centurions, Max, Jake, and Ace are appointed by the resulting single world government to battle Half Mad and his followers.
The characters all had alternate names considered: Max Ray: Max Proteus, Jack Finn, Scuba Ford, Sean Finn, Sharky Finn, or George Striper Jack Rockwell: Nat Stone, Arnold Stone, Terry North, "Demon" Frazier, Slate Rockwell, or Butch Moran Ace McCloud - Harrison McCloud, Bert Sky, "Mach" McCloud, Glenn Peters, Anthony Flyte, or Benjamin Flyte. Rex Charger: Rex Powers or Storm Larsen.