It's these dang p212x and p1496 WUs! They're not worth that many points, but they take forever to complete. As someone else pointed out, though, it appears we're all being slowed down at the same rate.
Other than my brother's two new Macs that are being assigned the new SMP WUs, I can't really give you any tips. I could shut down my other 11 machines, and his two would carry my load quite nicely.
Without checking, let guess: one of those is that infernal 5way_melt work unit, right?
Please consider getting more brothers