| Sarlax |
Since the Cinderlands are such a departure from Korvosa, I think you ought to double-down on how alien it should feel to city-folk. I just finished GMing this part of the AP and have some thoughts.
Make sure the Shoanti feel like a real culture. They should not feel like helpless savages just waiting for the PCs to fix things. The Shoanti should mostly hate these tishamek wandering into their territory expecting to learn their deepest cultural secrets.
Ditch the Boneslayer entourage. The Boneslayers make the Cinderlands less mysterious since they can just explain everything. They're also too fragile in an encounter that is level-appropriate for the PCs, which can cause some serious Respect damage if the PCs aren't willing to shell out thousands of gold when they almost inevitably die. Maybe, if the PCs feel incapable of navigating the Cinderlands, the Skoan-quah might grudgingly offer one, perhaps a novice, but make sure to really develop this guide so that if they die, it feels like a real loss. But it's better if the players are on their own since it makes things scarier for them.
I recommend making the "respect quests" more robust. I decided that Sun Shaman was under a geas-like oath that forbids him from sharing the truth with anyone who had demonstrated a commitment to the ways.
In retrospect, I would like to have made the big respect quests actually meaningful to the AP itself rather than just accumulating bragging rights. Otherwise, the PCs are just running around trying to look cool enough to learn a secret.
What I wish I'd done is put clues or MacGuffins in those sites. Here are some ideas:
* Amarund, the Shoanti member of the Palatine Eye Shoani who helped defeat Kazavon, returned to the Cinderlands after her quests. He (or she) scattered clues to his quest in his homeland.
* Amarund was a fire priest and died being devoured by a purple worm, which became Cindermaw. Cindermaw has some of Amarund's essence, and a PC who permits herself to be swallowed will gain some of Amarund's memories. Or perhaps an actual possession of Amarund's is in Cindermaw's gullet still.
* The Acropolis has a record of a visit from Amarund, who considered using Thassilonian magic to bind or destroy Kazavon for good. Consider making one of the statues an intelligent construct who can relay what Amarund was doing.
* The House of the Moon shouldn't be a happenstance visit, but rather a place to meat Desna's proxy, who can provide details about Amarund's life.
Definitely use random encounters and weather. The Cinderlands should feel wild. I had rocs swoop down to haul them away, ankheg swarms, basilisks, etc.
Drop lots of hints about the Cinderlander (and don't call him that). He's a high-level badass murderer who is able to survive in this place on his own. Consider having him set traps for the PCs, too.