"Astropolis" -- 8 lines,
From the prompt about star cities, I got the free-verse poem "Astropolis." It's a conversation between a young planet-dweller and an old spacer.
"Beneath Suspicion" -- 5 lines,
From your prompt about other creatures powering public transit, I got "Beneath Suspicion," a free-verse poem about an unexpected power source for the subway's third rail.
"Breathing People" -- 36 lines, $15
To your prompt about the growth and decay, I added one from akilika about why people move into or out of cities. The result is "Breathing People," which looks at cities as living creatures. I still had Detroit on the brain from whoever started that ball rolling, so the ending includes some rather disturbing imagery.
"The City at the Sun's Edge" -- 36 lines, $15
Your prompt about city spirits brushed against one by marina_bonomi on newly appointed city gods. I remembered a long-ago fishbowl poem I wrote about a human woman named Dawn, who brought civilization to an alien race. So it seemed natural to continue the story with them making her into the guardian-spirit of their first city. "The City at the Sun's Edge" is written in couplet-rhymed quatrains. (And in case you're wondering, "The Builders of Dawn" is still available; 12 lines = $10.)
"Feminists Under Glass" -- 32 lines, $15
From the "glass ceiling/glass houses" prompt I got the poem "Feminists Under Glass." It looks at how women's experiences and tactics have changed over time.
"Gaslight and Cold Iron" -- 20 lines, $10
Your prompt "Gaslight and Cold Iron" turned into the title of a poem, written in rhymed and metered quatrains. It's a rather creepy bit of steampunk, in which fairies are used as streetlights -- a musing on how progress in any society tends to come at somebody's expense, and the people who benefit by it usually don't care. The more things change, the more they stay the same.
"The Houses of Haunted Dolls" -- 33 lines, $15
I put "things left behind" with what janetmiles said about feral buildings. The result is "The Houses of Haunted Dolls," a free-verse poem describing what happens when diverse mythologies are left to their own devices in inner-city Detroit. When we forget that we are responsible for the things we build, the results can get scary...
"Perishable Truths" -- 27 lines, $15
I combined your prompt about magical creatures disguising themselves as machines with one from janetmiles about fae adapting to iron. "Perishable Truths" describes what happens when the fae begin taking forms that will blend into the modern world, just as they used to blend into natural scenery. Humans are a little too slow on the uptake...
"A Thousand Pokes of Failure" -- 66 lines, $33
I wrote you a poem based on your prompt about Titivillus, combined with what minor_architect said about beginning-of-semester woes [...] It is the history of Titivillus tormenting scribes, up to the point where universities start putting things online. You can imagine that this ends badly for everyone who is not a demon.
"Urban Shamans" -- 40 lines,
I liked the idea of urban shamans and painted designs. "Urban Shamans" is a free-verse poem that visits some representatives from four different cities and how their various cultural backgrounds blend into modern life. They work their magic in plain sight, filling the ancient role of go-between.