I love paying attention to detail too.
I already knew about the Charon thing, how he was connected to the figure in Greek Mythology who carried the souls of the dead to the underworld. It also makes sense that he works in a bar called the 9th Circle, which references the 9 gates of Hell like in The Divine Comedy (I've never read it, but a friend told me about it).
I noticed that Tenpenny Tower is based on Fiddler's Green from George Romero's Land of the Dead. It was a zombie film where zombies had taken over the world, and wealthy survivors were living in a large skyscrapper much like the hotel Tenpenny Tower is. The poor lived outside in a walled-in fort and zombies were starting to become more intelligent and figured out ways to sneak in, much like the ghouls did. The zombies broke in and killed all the rich people living in the building, but the poor people survived and decided to restart once the zombies left.
The one thing I hate about the movie and the quest associated with Tenpenny Tower is that they make it look like all rich people are evil and deserve to get devoured by zombies. Despite that I loved the reference though, as I like George Romero's zombie films.
I also noticed every song on Galaxy News Radio relates to the events in the game in some way. "Way Back Home" refers to how the Lone Wanderer misses Vault 101, "Crazy He Calls Me" refers to the companion Clover and how she's "Crazy in love" with whoever owns her, and "I Don't Want to Set the World on Fire" I think is pretty self-explainig.
I also noticed that there are certain NPCs you will find in every settlement. You'll always find a town drunk (Jericho, Micheal Hawthrone, Patches), a prosttute (Nova, Trinnie, Susan Lanchester), a junkie (Leon Stahl, Paulie Centali, Snowflake), an evil businessman (Colin Moriarty, Mister Burke, Azhrikal), a protective guard or sheriff (Lucas Simms, Chief Gustavo, Chief Harkness), and a robot (Deputy Weild, Shakes, Ceberus).