SPOILERS
Somewhat difficult to accurately predict at this point. Perhaps after some additional DLC content we may have a better idea.
As it stands now...
After my first playthrough of DAII, I couldn't help but feel as if this game were the first installment in a much larger story that has yet to be fully revealed, let alone unfold--DAII seems like it was a mere piece of a much larger puzzle. As such, I feel as though this story will continue in DAIII even after DAII DLC content is over and done with.
The game is essentially set around Leliana and Cassandra desperately seeking out the Champion, Hawke, apparently because they believe Hawke is their best bet in calming the Mage uprising that has swept the lands, given how much renown Hawke has earned--or so they claim (bear in mind, this is all assuming Hawke sides with the Mages, which I believe makes the most sense in terms of canon/continuity). However, they also mention something else that is rather obscure and ambiguous--"do we proceed with the original plan, or do we keep looking?" What might the original plan be? Either way, it was left rather open-ended as to what choice they made--a large part of me suspects they will "keep looking", however.
Varric claimed to be oblivious to Hawke's whereabouts when questioned by the Seeker, Cassandra, and he maintained that position throughout the story; but is he telling the truth? What reason would he have to lie? Well this is Varric we're talking about, a sly Rogue Dwarf who has been through thick and thin with Hawke, and presumably become a very good friend to Hawke. It would be uncharacteristic for Varric to betray Hawke's whereabouts to a stranger who essentially arrested and threatened him for information. I suspect Varric knows exactly where Hawke is, or at least has a pretty decent idea. Afterall, he claims to know that Isabela is still with him (though this may be dependent on romance choices?); how could he know that, yet not have any idea about where Hawke and Isa are going, or what they intend to do?
Then, of course, there's the mysterious Felmeth to consider. It doesn't seem likely her role in all of this is minor; in fact, it seems more likely that she's manipulating and orchestrating a good amount of these events in one way or another--though her exact means and ends aren't certain at this point. Either way, I suspect it's safe to say that her involvement is far from over. "Is it fate or chance? I can never decide." Sure, she could have simply been referring to the opportunity which presented itself for her to be carried to Sundermount for whatever reason--but since when has Flemeth been simple? It seems to me she wanted Hawke in particular to get safely to Kirkwall, and arrive at Sundermount. But why? Is it possible she foresaw the events which would unfold as a result of Hawke being in Kirkwall? If so, how could this chain of events be useful to her overall plans? She speaks of the "precipice of change", obviously foreshadowing events to come.
Lots of intrigue and mystery with this installment of DA. Lots of possiblities of what is to come next.
I suspect that Hawke may again be the main protagonist in DAIII as the Seeker, Cassandra, along with perhaps Leliana continue searching for him to acquire his aid. Obviously I hope Varric returns as well--Hawke without Varric just seems wrong. Perhaps after finding Hawke, and Hawke realizing the events that have unfolded because of what happened in Kirkwall (read: chaos, open war between Templars and Mages, etc.) he'll feel guilt-bound to try to mend that which he helped cause, and thus set out on a new quest to try to stifle impending war? It could happen.