Made several improvements to the Poltergeist enemy: they are now revealed on being attacked or hit with Radiant Spirit Guardians; they will not turn Invisible again if they are still in a character’s See Invisibility aura; in Balanced and Explorer Mode, they have disadvantage on Dexterity Saving...
None of the complaints you made here has anything to do with the FR as a setting. And btw the FR are a generic a fantasy setting withall kinds of fantasy tropes crammed into it. You go from classic high fantasy (Sword Coast, Dalelands) to arabian nights (Zakhara, Al-Qadim) to jungl...