I listened to all of the shows a couple of years ago, and I completely agree with your assessment. From what I understand, their white supremacy group episodes actually revealed things that happened in real Ku Klux Klan meetings and were deliberately designed to thwart that group.
On a lighter note, I never tired of listening to Bud Collyer change personas mid-sentence. His voice command was truly masterful. From what I understand, the producers had originally planned to hire two separate actors for the role (one to play Clark and the other to portray Superman), but when they heard Bud audition, they realized that he could actually perform both parts himself. A brilliant casting decision.
One other thing the radio episodes gave us: Up, Up, and Away! Superman said this phrase (along with other spoken "stage directions" such as, "Down! Down!") to help the audience envision the action. For a similar reason, he and other characters often spoke their thoughts aloud when, in real life, they would have kept quiet.
One thing I enjoyed about the show -- although I think they tended to overdo the gag -- was Clark/Superman having little slips of the tongue that would almost give him away, but that he would manage to cover up somehow.
I, too, recommend listening to the show.
Joy,
Lynn
