The Perils of Subgenre

I'm going ask an honest question: is subgenre as important in any other genres as it is in fantasy and science-fiction?  I mean, I really don't know how, say, mystery or horror is broken up, and if there is a significant difference in how supernatural horror is treated over real-world serial-killer kind of horror.  Or are those thrillers?  See, I just don't know.

My main problem with subgenre is trying to figure out where my work fits, exactly.  My sci-fi stuff isn't much of a problem, of course.  It's more or less Space Opera.  Sci-fi subgenre classification is pretty clean, especially since there's "New Weird" as a nice catch-between-the-cracks solution.  Though if someone out there has a sci-fi work that they have trouble classifying, I'd be intrigued to hear it.

Fantasy, however, isn't clean.  Especially since there are agents who differentiate which subgenres they will and won't represent.  I guess I'm just not clear on where lines are, and where I fall on the map.

Urban Fantasy?  I lean towards saying that my various Heroes of Maradaine books (Thorn of Dentonhill, Holver Alley Crew and Maradaine Constabulary) are Urban Fantasy.  Maradaine is a city, after all.  It's not, however, a city in our world, like New York or Chicago, and it's certainly not a version of one our cities where magic is real (and a poorly-kept secret, most of the time). 

Epic Fantasy?  I don't think it's "epic", not in the sense of scope or scale.  There's no riding from country to country.  There's no armies fighting each other.  Nations do not fall. 

"Traditional" Fantasy?  What does that even mean?  I'm not entirely sure.  I have no dragons or elves or trolls or vampires or other such trappings, if those are what make fantasy "traditional".  But I'm not even sure that's what it means.

Dark Fantasy?  I'm not sure what this is, exactly, but I know I'm not really here either.  Again, no vampires, no werewolves, no deep brooding, no tragic antiheroes.  Well, a little dark brooding.  And Holver Alley Crew has something of a tragic antihero. 

I've been taking to saying that, in terms of subgenre, what I write is similar to Scott Lynch or Amanda Downum, and hope that gives people an idea of what I'm doing.  Is that completely accurate?  I'm not entirely sure.  But for now, it'll do.