First off, I love the fact that the game changes things up by having one relatively small setting over a long period of time rather than a large setting over a relatively short period of time. It feels like a great departure from Bioware's normal style of traveling to many distant lands and it gives the opportunity for you to see the consequences of your actions over time rather than waiting until some end of the game epilogue. It also provides the opportunity for subplots to develop and have more depth because a lot of these subplots don't get resolved right away.
But one of the ways that the game stumbles is sort of related to the increased importance on supporting characters. Despite the fact that the game stresses the importance of the player's decisions, it feels like too much of the plot is just out of your hands. I get that it's to make the game world feel like a real world, and to make the people in it feel like real people who make their own decisions, but at the same time I think it undermines the importance of the player. When the game spends so much effort trying to reinforce the importance of the player character, it feels contradictory when things seem to turn almost exactly the same no matter what you do.
Also, while I like the fact that Bioware seems to be keenly aware that this is a franchise, and they're setting up a larger conflict that can't be contained in one game, I feel like they're relying too much on the fact that they're going to have a sequel. They spend so much time building up plot threads for future games too much of it feels unfinished.
The developers have gone on record saying that the protagonist of this game, Hawke, is meant to be the single most important character in the Dragon Age universe. But while this may be true, events tend to unfold because of Hawke's presence as often as in spite of it, things often feel completely out of your control. Once again, I get that Bioware is trying to make this feel like a world with real people who have has much influence as Hawke, but this is Bioware we're talking about. All of their games that I've played have placed a strong importance on the player character, and the player in particular. Your actions shape the game and the world the game takes place in, but in this case it feels way too railroaded.