Might you consider broadening it to "Weasley/Deatheater?" That would include Ron/Snape or Percy paired with Snape, Draco, Lucius, etcetera.

But after seeing a Ron/Narcissa pairing I thought Ron/Lucius would be a natural (pureblood pride!), and there just ain't anything decent (or suitably indecent) out there with that pairing...

I've never participated in a ficathon, don't know whether I could write smut or Weasley POV, but I'd be willing to give it a shot if I could get Ron/Lucius in return...