Harsher in Hindsight: The near crash of the space shuttle Columbia, until Ralph catches it and brings it down intact.
Also, the 2nd half of the pilot involved Ralph Hinkley attempting to thwart the assassination of the President. The pilot aired on March 18, 1981; almost exactly two weeks before John Warnick Hinckley's assassination attempt on President Reagan that forced (among other things) the temporary name change to "Hanley".
Life Imitates Art: In "My Heroes Have Always Been Cowboys" Ralph repeatedly states "I grew up on this guy!" regarding The Lone Ranger. Now a lot of people who grew up in the early 80s say the same thing about Ralph and GAH.
Nightmare Fuel: The show was generally pretty light and fluffy, but occasionally..
The murder victim in "Operation: Spoilsport" who gets reanimated by the Suit-bestowing aliens and abruptly looms up into view as a white-faced zombie/ghost.
"The Beast in the Black" features, yes, a set of giant disembodied chomping teeth zooming around in a lightless void.
Special Effect Failure: Averted in the minds of some viewers who feel the television budget obvious green screen and reuse of scenes have the side effect of nicely parodying the Superman Movie's 'You will believe a man can fly" effects.
The sea monster at the end of "The Devil in the Deep Blue Sea" is a laughably bad hand puppet that thankfully only appears for a few seconds.
With the set up before the appearence (Maxwell poopooing the idea of the monster and Pam convincing Ralph to give up the search as they both go below decks), it would have been much more effective to pull back to the monster's P.O.V., hear the sound of water parting, and watch Maxwell's reaction.
They Wasted a Perfectly Good Plot: Ralph losing the second instruction booklet. There could have been a ton of scenarios involving Ralph learning the full capabilities of the suit, while still maintaining the mishaps that made the show more than a conventional action adventure show (when Ralph begins to read the second book, he displays the ability to shrink and becomes smaller than an ant, but can't figure out how to return to normal size), but he loses it by the end of the episode.
Debatable; letting Ralph kept the instruction manual meant that he'd no longer have a reason to be incompetent at super-heroics, and thus risk turning him into a Boring Invincible Hero.
"Weird Al" Effect: Parodies of the theme song, basic plot, and the goofy looking Hinkley are well known among people who were born years after the show ended and have no idea what is even being parodied.