The epilogue slides seems to be true. Morrigan did go to Orlais. There were Wardens waiting on the border between Ferelden and Orlais and she could have shagged a Warden we don't anything about. If the developers want her to have a child regardless of your choice as a player then she will have one.
If her child is an OG his powers might be unlimited from what we've seen so far in any game. We've seen in DA2 an eluvian can change any characters looks and this also includes their sex. I've always considered the explosion on top of Fort Drakon as the Maker actually killing the arch demon. A massive amount of power is expelled from the sword strike which unleashes it. To me the Maker is the one who always killed the Arch Demon and Meredith in DA2. The Warden and Hawke are always given credit for it. As the Warden and Hawke you give the Maker the opening to kill his enemies.
We also know by Merrill and now the Masked Empire that all of the Gods seem to be at war with each other, I can't help feel this will play a part somehow.
Also is that the temple at the urn at around 40 or would any of you say it's Dragon Bone Waste?