I think this is a bug, but I am playing 1.3 as an adept/paladin and mage/battlemage/warlock. Well, I had my first four character slots filled and I went back to the Guild of Mystery in Fargrove and asked about the Guild of Mystery. She asked if I wanted to join, I said yes and paid the fee. This was after the mansion, of course. I was told to deliver the treasure map to the guy in Skuldoon. I delivered it and I got the old good job and I got to choose another heraldry to add to my list. I never got any ability to go on another quest for them, but I thought the extra heraldry was neat.
I now have more than ten heraldries (I think 12 or 13, but I do not remember). It would be nice to know if they do help and if having more than 10 is OK, meaning do they just keep the 10 best for you or what.