Well, ultimately your gut has to be the judge. I have my own biases and opinions and gaps in knowledge. I might say "what's Dickens doing here?" because, based on whatever Dickens novels I read a million years ago, my idea of Dickens is ragged waifs and bleak scenes of poverty and whatnot. You or someone else might think, well, duh, Dickens, ghosts of future, past, etc., and think it works perfectly well. Ditto for Cain--I think the connection is tenuous at best. You or others might disagree; find connections I don't see.
What I will say is this: if you're putting in extratextual allusions simply to justify a detail--e.g., referencing Dickens as a way to provide context for shawls and scarves--I don't think that's a good enough reason. There are better ways to do it that don't distract and provide more balance or ballast or whatever in the poem. And when you get to the stage where you've figured out how to fix most of what you didn't think worked--that third draft stage or whatever--put it aside and grow some distance. Then go back and see what jars, what people said jarred them, etc., and then have a go at tweaking it.
Anyway--Ranger Nightingale. What kind of hitman name is that?
http://www.biovox.com/generators/hitman.
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