Regarding the title, I'm not sure if everyone remembers this but it's another classic Cardassian literature reference, like Una's previous book The Never-Ending Sacrifice.
Meditations on a Crimson Shadow was another book that Garak recommended to Bashir as a classic. I'd say it's much more likely the title is a reference to that than to human noir thrillers. Although I guess it could be both.
Another cool note on the title, its referenced in the Cardassia: The Lotus Flower.
Towards the end of the book, when Garak is walking home, it goes: "Dark skies and darker dreams, but still the city of crimson shadows