I just got back from DragonCon. I stopped and spent time with my mom before heading back to work. I did manage to ask several of our questions, but couldn't get them all in. Sorry, if I snubbed your questions. I already felt a little rude asking four. Either way, I really hope someone got video and gets it posted.
Highlights
I never asked but it seemed to me that the original cast of characters would remain central to the plot of the next book.
Yes there are Female Warriorborn, Warriorborn makeup ~2% of the avg population, More on warriorborn Below.
The avg lifespan of a Cat in the Cinder Spires in 60-70 years. It is comparable to humans in the CS.
A Commodore cat is coming and is slightly better at everything than Rowl. Which Rowl cannot allow. Also possibly a very small and aggressive one might appear as well.
There are a few more type of crystals but we have seen the most common. Trim crystals are simply smaller Lift crystals. I imagine the "rare" ones are cool and plot relevant.
It is possible to reverse the polarity of a ship and its webbing, so to speak, and have the ether push instead of pull the webbing when powered but would essentially be rewiring the entire ship. Generally it is simply easier to ascend or descend a few hundred feet into a different etheric current.
The 3 seashells moment would likely involve something similar to a sponge or leather scrappings. Rather Roman-esque.
The spires are not identical. In fact, the Pikers actually live on a mountain and are on constant guard against "things" that come up the mountain.
Many of the warriorborn, male and female, live at the base of the spire as farmers and woodcutters. There are regular people but they are each extremely dangerous regular people. There is apparently a plant similar to kudzu as well.
Jim got a specialist to assist with the venting calculations and the amount of vent space is rather large but actually needed for a structure the size of a spire.
The Biggest reveal for me was
The major arc of the series is that the tech that has been sustaining life in the spires is starting to break down. It is worse in Aurora than Albion. He also mentioned that the Britain/Spain = Albion/Aurora corollary is less strong than it appears but we'll see more about that in the next book