Throw It In: The dog talking back to the Storyteller was a happy accident. Anthony Minghella just assumed that a dog in a Jim Henson production would talk, and wrote him that way, though Henson had said nothing about whether or not the dog would talk.
What Could Have Been: Press release material mentions an episode that involves an ogress keeping a princess captive, which seems to be based on the Italian folktale, "Petrosinella" (an early "Rapunzel" variant), but it has never been released, or likely ever made.
A finished but unproduced script was a retelling of the Russian folktale "The Witch Baby", and would have included the Storyteller and his tarot-reading abilities as part of its events, as in "Hans My Hedgehog". The story of a prince who must confront his demonic cannibal sister (who can grow to the size of Godzilla) was adapted into the 2011 graphic novel anthology.
It has also been confirmed that an episode based on Vasilisa The Beautiful (a Cinderella variant with Baba Yaga as the Wicked Stepmother) was also in development. The unused teleplay will be adapted into a comic book for "The Storyteller: Witches" spin-off.
Henson planned to expand the show to have hour-long episodes, allowing for more complex stories and more time to show off the Creature Shop's work, but the show was cancelled before any could be made.