You know what idea I've been toying with since I first saw the trailer?
So you know how the weird glowy maybe-Andraste figure is standing on the top of a flight of stairs? Well, the summit is at Haven. Isn't the Urn of Sacred Ashes at the peak? On top of an albeit short staircase? (Inside the room anyway, on a pedastal thing. It's been a while since I played that quest.)
I dunno, it isn't even really an idea at this point, mostly conjecture, but could they be connected? "Herald of Andraste" and all that. There was apparently an insane amount of lyrium etched into the walls of that room, perhaps that affected the Inquisitor's experience in the Fade somehow? So even if those aren't actually her ashes and the weird glowy figure isn't actually Andraste...
:S Again, rambly incoherent conjecture. I'm sure I'll be able to come up with something more coherent eventually, but I thought I'd throw it out there.