In addition to the great suggestions above I pull a lot from Celtic/Gaelic mythology. The Sidhe (or Aos Si) are the rulers of the land with the different courts with the Seelie court being beautiful and the Unseelie court being ugly and deformed.
Both are equally dangerous in their own ways. The Seelie court is associated with spring and summer, but they tend to enchant people and make them forget their mortal lives. A night in the Seelie court may last for decades in the real world. The Unseelie court are where goblins and their kin come from so basically any deformed humanoid like ettins fit the bill. I also use modified aberrations on occasion.
Throw in the wild hunt, faerie mounds, so on and so forth brings the Feywild to life for me.
I don't worry too much about what monster I user for the Sidhe. I usually base them off the powers of some extra-planar being, either celestial or fiendish depending on their role.
Both are equally dangerous in their own ways. The Seelie court is associated with spring and summer, but they tend to enchant people and make them forget their mortal lives. A night in the Seelie court may last for decades in the real world. The Unseelie court are where goblins and their kin come from so basically any deformed humanoid like ettins fit the bill. I also use modified aberrations on occasion.
Throw in the wild hunt, faerie mounds, so on and so forth brings the Feywild to life for me.
I don't worry too much about what monster I user for the Sidhe. I usually base them off the powers of some extra-planar being, either celestial or fiendish depending on their role.