I could go with something besides Deathwatch, such as an Astartes impressed into assisting an inquisitor as part of their retinue. That way it would provide backup to a non-Ordo Xenos inquisitor. I think it best to hold off on a choice until we have another inquisitor around that could use that sort of backup. I really am leaning Blood Angel, Dark Angel or Death Eagle because there are deep currents of potential intrigue in there. But I'm going to take the cue from a partner on this moreso than just throw a character out there. I was considering a Space Wolf also, because they make everyone a little uncomfortable, but someone else mentioned those and I think a Space Wolf is always a good thing to have in any plot.