The town in the pit sounds awesome and is a cool idea (I'm going to go read Edgedancer since you mentioned it), but I'm not sure if it fits in with the rest of the map you've done so far. The mountains are absolutely gorgeous and the line work all around is so clean it makes me smile

For the ocean/coasts I remembered looking at this the other day, might serve as some inspiration, but it may just add too many lines to the map and muddle things a bit: https://scholarcommons.usf.edu/litbookarts_gallery/289/