I think what makes people most agitated is not the fact that Hawke returns, he should. But the fact that the low amount of attention the warden gets. The warden is a important character who had a impact on people as well as history. There are people who favours the warden. but bioware doesn't want to pay attention to them.
Bioware is so desperately trying to make the Dragon age universe without the warden.
There hasn't been any message or statesment to the fans saying that they pay intention and are trying to make it significant story.No dialogue from Bioware to open a discussion or showing to warden fans that they are not forgotten.
But by doing this throwing breadcrumbs and hope that is enough.....hugh
But that's just it: importance. The Warden is important - during Origins. The Dragon Age universe can exist without the Warden; implying otherwise would be a bit of a slap in the face to those who made the ultimate sacrifice, and like I said, the world of Thedas is a big place, the story should be focusing on the world and its mysteries, not the characters, otherwise, we may-as-well have a Commander Shepard each game. The Warden may not be important now, but they proabbly will be later (particularly due to Bioware dropping hints of something being built up to), and Hawke is being used now because they are important. And all of this is for the benefit of storytelling; what you're asking for is fanservice, and wanton fanservice was a large complaint of DA2 - in fact, many people said that the cameos made the world seem smaller than it needs to be, emphasizing my argument above.
And I'd just like to reiterate one of my last notes; the Warden is no longer ours. It's Bioware's property and they know best where the story is going to lead, and it's best to play the game first before passing judgement.