Fair for Its Day: While the depiction of minorities is hardly perfect, Native Americans are treated with far more respect than usual works of the time period allowed for, and Asian characters were generally treated as respectable, law-abiding citizens... when Yellow Peril wasn't in play.
Older Than They Think: Most people attribute the Fleischer cartoons as the series who gave Superman the power of flight, but it was actually the radio show that introduced the concept a year or so earlier.
The Scrappy: Finding a modern listener who enjoys Poco is difficult. A squeaky-voiced character who always speaks in rhyme and claims that speaking normally causes him pain, there are several points where he can't tell the heroes important things because he can't think of rhymes. Couple this with his naivete and you've got quite an irritating mix.
Signature Series Arc: "The Clan of the Fiery Cross" is by far the most well-known arc of the radio series, to the point where it is famous even among people who are not familiar with the rest of the series. It was even given a modern reimagining in comic form.
Values Resonance: "The Clan of the Fiery Cross" has messages that still hold up well;
Americans of different races and religions deserve the same respect as everyone else.
Do not give into fear in the face of violence and intolerance, you will only give your oppressors what they want and let them get stronger.
People who exploit racial tensions care more about power and money than any kind of ideals.
The storyline more than once compares the Klan tothe Nazis. As Ku Klux Klan and other white supremacist groups have become increasingly tied with the Neo Nazis, this comparison proved highly prophetic.
YMMV for the television show:
Alternative Character Interpretation: In one episode a gangster and his moll discover that Clark Kent is Superman. Superman's solution? He leaves them stranded on a snowy mountain until he can figure out what to do with them... and then they fall to their deaths while arguing. Did Superman do that on purpose, hoping they would kill each other while fighting, thus preserving his secret?
Complete Monster: Lou Cranek, from season 1's "The Mind Machine", is a major crime boss being investigated by a Senate subcommittee for his illegal activities. Cranek kidnaps a scientist named Edward Stanton and steals a device Stanton invented that would use hypnosis to help mental patients. Cranek, who wants Stanton to use the machine as a Mind-Control Device, forces Stanton by knife point to force his former accountant to change his testimony in front of the committee. The accountant then goes insane, hijacks a bus with school children on it and nearly drives it over a cliff. Superman saves the children, but the accountant dies, the machine having destroyed his mind. Cranek uses the machine to silence and kill 2 other witnesses. When confronted with these deaths by Stanton, Cranek states he does not care and will use the machine himself when Stanton refuses to. Cranek plans to kill Stanton after he no longer needs him and plans to use the machine to silence the final witness against him, Lois Lane.
Harsher in Hindsight: George Reeves died less than two months after the series' last episode aired. At the time, almost all his career options involved playing Superman, a role he had come to tire of (he reportedly never liked the job to begin with, seeing as it was the 1950s and neither TV nor comic book superheroes were seen as the potential money makers and career franchise builders they are now). Thus, the exchange between Jimmy and Superman in the show was chillingly prophetic:
Jimmy: Golly, Mr. Kent, you'll never know what it's like to be like Superman. Superman: No, Jimmy, I guess I never will.
