I ran out of time while writing Refuge Beneath the Waves
(it was a self-imposed time restraint, but still) and never managed to do as much with it as I would have liked. I doubt I'll have a chance to go back in anytime soon and add those details.
One of those details, which has been mentioned in comments both on and off the site, is the people and their lives. With that in mind, I'd like to open it up for someone else to write a sub about the people who live under the sea. I'd like to see where someone else could take this idea.
To make this interesting, I will open it up to a negotiation. Anyone interested in writing this can propose something similar for one of their own subs. If you want to expand on Refuge Beneath the Waves and
have a sub of your own that could use a related sub for fleshing out, please respond below with the name of that sub and the area you'd like me to expand on.