Canon Fodder: Loads of it; for example, Gadget's past and the fate of her father has never been explored.
And what about what happened between Monterey Jack and Gadget's father? Or what Monterey Jack was doing before he met the Rangers (and how exactly he got those "cheese attacks," because they don't seem to me to be something he got from his parents [both of whom appeared during the show's run]).
Genius Bonus: Monterey Jack is obsessed with cheese. Monterey Jack is also the name for a blend of cheese from Monterey, California. This leads to a little bit of Fridge Logic when you consider that he's Australian, but named after a cheese from California.
Fridge Brilliance: Both of Monty's parents (Camembert Kate and Cheddarhead Charlie) are travelers and adventurers. Maybe they were in Monterey, California once and named him then.
The voice Jim Cummings uses when he plays Monterey Jack's father Cheddarhead Charlie on the episode "Parental Discretion Retired" is actually the voice Cummings used to play Monterey Jack after Peter Cullen left the show. "Parental Discretion Retired" was one of the early episodes that had Monterey Jack voiced by Peter Cullen.
In "A Wolf in Cheap Clothing", Jim Cummings voices a Tasmanian devil. A couple of years later, Cummings would become the voice for theTasmanian Devil (as in, the Looney Tunes character)
Monterey Jack talked a lot like Steve Irwin already before the latter was even known outside Australia.
In the episode "A Lad in a Lamp", the genie is voiced by Dan Castellaneta. The episode predated Aladdin by three years and is funny because Dan Castellaneta would become The Other Darrin for the Genie in the Aladdin animated series due to Robin Williams having a dispute with Disney.
Ho Yay: Dale during the drag act in Adventures of Squirrelsitting. He's clearly enjoying his disguise and is flirty with both Chip, Monthy and even Fat Cat.
Monthy: I'm sorry, pallies. But Gagdet needs some cover.
Dale: No problem! (winks and rotates his shoulder)
Foxglove from "Good Times, Bat Times". Foxglove has an entire website devoted to her (and now dedicated to her voice actress, the late Deborah Walley).
Tammy and Bink from "Adventures in Squirrelsitting".
Queenie from "Risky Beesness".
Sparky from "Does Pavlov Ring a Bell?"
Geegaw Hackwrench from "To the Rescue, Part 3" isn't even really a character, he is only ever shown on a picture. Yet, despite his unknown fate and total personal absence, he is quite popular in the fandom.
Shipping: Chip/Gadget, Dale/Foxglove, et al. If there's even one hint of a ship in the series, someone's supported it somewhere in the fandom.
Ship-to-Ship Combat: The debate over the Chip/Gadget ship led to two flame wars known as the Ranger Wars (one in 1997 and the other in 1998), and it will probably never be settled.
Anticlimax Boss: While the first game as a whole isn't too hard, a number of the bosses (including Fat Cat) barely move at all, and are highly predtaictable.
Even Better Sequel: The second game isn't as well known due to being released so late in the NES's, but it improved on the first in nearly every way possible, from graphics, to gameplay, to having a story that would not be out of place in a multi-part TV episode.
Game Breaker: In the second game, proper use of the fastball special makes most bosses incredibly easy.