The Ghostbloods are wierd. They are the most mysterious secret society on Roshar (that we currently know of), and probably the most dangerous too. The Sons of Honor wound up being a non-factor (their one on-screen member is dead) and the Diagram, while competent, is currently being absorbed into the forces of Odium, and hasn´t really had the huge amount of success they expected. But the Ghostbloods are still out there, and hasn´t even made one major play yet, as far as we know. I thought a bit about Mraize recently, and suddenly, I got an idea: what if Mraize is the Head of Information in the organisation?
So, why would Mraize be the Information-boss? Well, first off, he knows a LOT. He knows everything about the Skybreakers, he knows of Shallans family, of the Diagram, of Amarams involvement with the Sons of Honor, of Ashs madness and of Talns location. That is an incredibly extensive list. Second, whenever we see him, he is trying to obtain information of some kind. He is constantly sending Shallan to spy on various people, or, in OB, to find Re-Shepir. He is himself seen spying on Ialai. He is undercover in Dalinars army during the Battle of Narak as well, and interrogates Ash, presumably for some kind of info regarding Heralds or the Oathpact. More or less everything Mraize does is about gaining information. We also know that Mraize is a title, and a title generally comes with some kind of position. What if a Mraize is a master spy/Head of Information?
If Mraize is the Ghostbloods major information guy, the powers of his Aviar would probably relate to information-gathering as well. I believe that the birds powers is either the powers that we see Sak having in Sixth of the Dusk (being able to warn its master of eventual death) or some kind of power relating to sensing danger or emotion. If we look at the birds interaction with Shallan in OB, it chirps at her twice, both times when she appears to be angry at Mraize, or threatening towards him. Having an aviar that works as some sort of warning signal, wether through sensing emotions or warning of general danger, would be of great use for a spy like Mraize.
I don´t know how reliable this is, or even if it is important, but I felt like posting it, in order to see peoples reaction.