Tarman & Thymara are still 'thul's favorite characters, though Leftrin certainly climbed quite a bit up due to his treatment of the greedy Cassarick/Trehaug councils and the stylish departure.
Thymara is much because she's to some small degree a bit naive, yet undeniably also because she's winged. Tarman for much same reason as leftrin, but also because he accomplishes so much without true speech.

These beings have a theory on why the city came to life with Sintara and not for Heeby/Tintaglia... Those two visited it alone. Sintara visited it at the same time as another dragon was there. She was also more queenly in her bearing than either of the other two. Heeby was lacking in knowledge, whereas Tintaglia is plain selfish. Another key part is that Kelsingra is a city of the Elderlings. She entered a place of their construction beside her own Elderling, both fully knowing just what they entered.

Selden's capture is an interesting situation, but it clearly sets things up for the final book.

Tintaglia's arrow wound is also such a setup. It will humble her before the Elderlings. Where both she and Sintara have the pride of dragons, only the latter truly knows to value Elderlings for their full worth. The humbling will teach her to not just demand, but to give. No doubt the Elderlings will demand that she help the Khuprus child in return for treating the wound. Sintara was naturally humbled by her initial lack of flight. In the old days, a queen like Tintaglia would have been humbled by the rest of dragonkind. In the new era, there were no elders to humble the newly risen.

Similarly, Icefyre is being set up to be humbled in BoD. He is no doubt sure that Tintaglia is his without even the thought of a fight. His age, wounds and various weaknesses puts him at a great disadvantage in a possible mating fight, possibly so great that his experience will not be enough to win.

It was highly interesting to learn that not only had dragons been ridden before, but they had been ridden to war.

More spoilers will follow later, when the new memories have been absorbed further.