Since Bron (Novahkiin) Martes seems to enjoy dodging responsibility have you thought of making a new character for the dark brotherhood quest line?
No, not really - after I created Laraniel I decided that three Skyrim characters would have to do. Currently Bron is a member of only one faction, and I fully intend to drag him into Dark Brotherhood matters (he kind of got tangled with them already anyway).
Besides, I’m genuinely interested in seeing what happens when you throw someone as dastardly as Bron into a situation like that. I mean, Brenna was basically made for it. Meirami (my potential candidate for TESO assassin) isn’t exactly shy about bloodshed either, and she has a bit of a reckless streak. Bron doesn’t quite have the typical personality/skillset for an assassin, but he initially calculates that it’s probably more useful to be on Brotherhood’s side than against them.
My in-universe reasons for his joining have to do with his rocky relationship with Maven and the rest of the Black-Briar clan. Her insinuations about having Dark Brotherhood connections and not being afraid to use them eventually leads Bron to consider that as a member of the said faction he’d probably be able to hear about (and perhaps even prevent) such course of action - preferably before he ends up with a dagger between his shoulder blades. And as it happens, he already has a standing invitation to join due to the incident with Grelod. “Oh, you got connections? Well, I got connections of my own. See how you like that.”
Still, knowing what DB was like in Oblivion I fully expect him to go NOPE at some point of the questline. It will be interesting to see how far the man can be pushed until the scales tip from “I don’t wanna piss these people off so I’ll just play along” to “you know what, scratch that - this is messed up and I cannot”. So, yeah, I doubt Bron will like any of it. I, however, look forward to the adventures of the Reluctant Assassin. :D