Running SKT and RoT concurrently. Nightstone takes place during the time of the First Council. So I had Zephyros's tower attacked by the Cult of the Dragon instead of Air Cultists.
With regards to Zephyros's Communes I explained he would see visions, a chessboard, where one side was shrouded in darkness (the enemy) and the other in light (allies). Many of the chess pieces would change each time he Communed, except for a few (the PCs). The chess pieces were sometimes represented by sigils, insignia's (factions), riddles and metaphors. He realised early on that direct action on his part would yield negative consequences because when he once tried to lift/grab an allied piece, the piece itself transformed into gas/smoke in his hands and was never again represented on the board.
What little he has delved into the identity of the enemy has yielded images of dragons, which he believes is associated with the Cult of the Dragon.
We recently ran the Goldenfields section.
The character who had the opportunity to play Lifferlas during the humanoid attack had a blast, he slew three bugbears fairly easily, the last one wolverine-style with his branches tearing straight through the flesh of the humanoid. He then found himself surrounded by just under a dozen or so goblins with torches between the residential longhouses. He used his incredible size to roll/climb over an adjacent long house, damaging it some, only to come face to face with a hill-giant who was scooping up corpses (humanoid or residents) and using them as a makeshift clubs, every once in a while refreshing his club with a new corpse.
At this point the humanoid attack was failing and there was a general call for retreat. The hill giant was doing minimal damage against the Awakened Tree and so attempted to make a run for it. And that is when the player said Lifferlas was going to grapple the Hill Giant and that he did, grappled and restrained him till the cavalry arrived.
Needless to say, everyone had fun playing the NPCs. I allowed them to use Inspiration with the additional characters if they could link their actions to any of the Ideals, Bonds or Flaws as stipulated on the NPCs. One Inspiration use per each during the encounter.
So far this AP has been nothing but spectacular.
Some additional notes:
(1) I had the tressym become attached to the elven ranger character in the group, funny enough he was the one that encountered the winged-cat first;
(2) Introduced Felgolos, as others have advised, who took an instant liking to the sibling, Bahamut-serving characters (Paladin + Divine Warlock);
(3) Had Kella Darkhope, Xolkin and one of his Snakes survive by fleeing the battle for possible re-occurring villains;
(4) Had the orc tribe, Long Ears, hide out in Nightstone's inn when the PCs made a foray into the caves. When the PCs returned and discovered the orcs - the party was torn between burning the inn or negotiating the orcs's peaceful withdrawal from the town. In the end cooler heads prevailed and the withdrawal was agreed to. This was a terribly bitter move for the elf in the party who recognised an Eye of Gruumsh amongst the withdrawing orcs.