I have to say that the title and the whole concept was really really cool. But, the rags themselves could've used more variation, specially rhythmical. You also could've gone a little further in harmony, and there is some strange stuff like direct transpositions and stuff which don't sound very cool. My favourite rag was Alkmaar, it's pretty cool.
But yea, more variation, specially if you hear them all one after the other it gets very tiring to hear the same exact bass line figure.
You didn't write any dynamic or technique markings, which I thought was lacking. There are a great deal of places where dynamic changes could've done a lot (repetitions, for example.)
I thought this would sound more Noir-esque or cabaret-german noir like, but well. I still think the idea is really awesome, maybe too awesome for what you wrote really. I couldn't really feel the concept reflected in the music as much as would've liked. And it's a cool concept, so that's a shame.