Rumpelstiltskin/YMMV

Alternative Character Interpretation: Was Rumpelstiltskin a malevolent entity who regularly make deals with mortals of dubious morality? Or was he simply just a mercenary of sorts who simply just wants to collect on what his clients agree to pay him?
Designated Villain Rumpelstiltskin. Up until the final act he really is not evil. It wasn't until the protagonist choose not to up hold her end of the bargain that he became an antagonist. Some tellings amend this by having Rumpelstiltskin not tell the protagonist what she'd have to give him in return for his help up until he's ready to demand it.
Family-Unfriendly Aesop: The girl refuses to keep her end of the deal and only wins against Rumpelstiltskin by spying on him. Rumpelstiltksin holds up his end of the deal and gives her a second chance out of the kindness of his heart, then dies a horrible death. The moral of the story? Cry and cheat to get your way, apparently.
- Then again he demanded her child as payment for helping her. God knows what he wanted to do to the kid.
  - A common interpretation based on his song is that he planned to eat it. However, while an easy conclusion to leap to, this isn't actually stated in the verse.
  - Considering that he was likely some kind of fae, it's entirely possible he wanted the child to, well... have a child. In many stories about fae they don't so much have baby fae as take human children and turn them fae.
  - Regardless of what his intentions were, she accepted the terms of his deal. She was, at least for a time, willing to throw her firstborn under a bus to save her skin for at least another night.
- The miller's daughter is threatened with death and ordered to complete an impossible task. If she reveals that her father was telling tall tales, he'll probably be killed. After three nights of this psychological torture, she is forced to marry and bear children for the king, the man who kidnapped her, threatened her with death, and locked her up for days. She then spends the rest of her life petrified that the king will find out that she and her father are liars. (Lying to the king is an act of treason, and the punishments for treason were pretty nasty back in the day.) With Rumpelstiltskin dead, what happens when the king's treasury is low and he asks his wife to spin more straw into gold?