Couldn't agree more. Which is why I really hope you can take DA:O's PC all the way through these games (However many there end up being). Much like you played the same Child of Bhaal throughout all the Baldurs Gate series. DA certainly has a plot scope that could easily accomplish this.
You are ABSOLUTELY right on the character writing..they did a fine job, so much so that everyone is going to miss their companions big time, be it because of romance, hard won friendships...or battle buddies.
Also agree completely. This is the first Bioware game I've played, and I'm incredibly impressed by the character development. The thing that gets me is this: would they dare try to develop a canon story, considering the nature of the first game? There are some things that can be written off or ignored, but other things are very difficult.
For example, let's say you're a male human noble in a relationship with Leliana at story's end. They can tie that one up easily without repercussion, because it's an aside to the main plot. It doesn't change anythign drastic going into Awakening. However, if you're a female human noble and get into a relationship with Alistair, and take that to the happy-ending conclusion, you're in a position of power and extreme relevance to the main storyline. Changing the details of that for the sake of canon would be pretty bad, doubly so because of the number of details they stuck themselves with in that particular ending.
That's really my biggest fear, and the only thing that would kill the story for me: a gratuitous lack of continuity. Being realistic, I think there's a slim chance of this happening because in a recent interview with a producer the poor guy had a huge grimace when he mentioned the one particular circumstance where you shouldn't be able to bring your character back, but they're allowing it. But I still worry, and I hope they stick to their guns even though developing multiple stories is difficult. It really shouldn't be much more complicated than dealing with all of the origin stories.