Is there more info on the Malfian Bloodsworn other than the splat in the player's guide? In particular is there a description of the Guild Badge that chartered members get? If not, what do you all think a Bloodsworn badge should look like? Also, how much authority should Bloodsworn be able to wield outside of the Malfi sub sector?

They shouldn't get any authority, just legitimacy. They're bounty killers not part of the state. They may get limited help or infoprmation from local law enforcement, then again they may not, it depends on the local cops. They've got a few (guild) contacts, a liscence to bounty hunt and their reputation to use, that's all really; and that's only within the Malfian sub. Drussus Marches = a Malfian what?