Mike Laidlaw has given a fascinating interview to Eurogamer magazine. WARNING: MILD INQUSITION SPOILERS
Laidlaw reflects on what went well (and not so well) with Inquisition, and gives some hints about DLC plans. As to content of DLC, he states: "The two big pulls are - 'I want more of this game' and 'I've reached the ending and I want to know more about the characters, or one specific character'," Laidlaw says. "I don't want to go into too much detail but I'm well aware of both of those camps and I'd like to see both of those groups satisfied before we're done."
As to timing for the DLC, Eurogamer states: "We won't spoil the post-credits scene here, but it sounds like BioWare is planning on telling at least a little more of that story sooner, rather than later."