Well, overall i liked it. I still prefer the DLC's that connects to the main story (Return to Ostagar, Stone Prisioner, Warden's Keep), and obviously Awekening, since i really liked it and consider it a propor expansion (even tough i felt the ending with the Architect a bit rushed). Really hated DarkSpawn Chronicles (despite the good ideia) and Leliana's Song (felt the story horrible and shallow).
At least for me Witch Hunt had very good aspects. I liked the companions, the funny aspect of the dialogues, the places they choose to use again, and the references to past facts and objects (look the coincidence, today i started for the first time a mage, and found it really cool to see Bioware using the Tevinter Statue in this DLC!).
Unfortunately Morrigan didnt answer very well the questions i had, but thats because i was expecting a full and troughly explanation for all the events. Overall it was good, and i liked the idea of having "another world" in this universe, and that "worse things existing". I was expecting for DA2 a plot more focused on politics, but i thing i can be wrong. This fantasy of DA is one of the most inteteresting things in the universe for me (like the fade).
About the "bug" in this DLC, it also happened to me. She said we had a son, but that i rejected her. My choice when i first finished DAO was to perform the ritual with her, so it was strange to read that things she said. What is curious is that i've never chosen the option to sacrifice myself, but when i imported my character for Awekening, that achievement (Ultimate Sacrifice) unlocked just at the beginning, i tought it was a bug, but didnt care... now i thing that maybe that thing "corrupted" my character story... the son that i had with Morrigan was because of the sex we had, but the child isnt a god or something like that, and so it would make sense what she said in this DLC. I will try now to import directly my character from DAO, and see if the bug iN WH continues. Did it happen to someone else (unlocking the ultimate sacrifice when importing character for awekening)?