I'm very curious what will be revealed tomorrow.
In terms of Origin characters the final art work in the video where tophat is behind the dragonborn with his hands on the dragonborn's shoulders and a cloud of claws and barbs behind him (0:55) makes me wonder whether the dragonborn had any agency at all. It may be like Astarion where the dragonborn is freed from Top Hat by the presence of the tadpole.
I agree, in this picture, it does look as if the Dragonborn is controlled by Top Hat/Fel. And with the red eyes, the Dragonborn looks "possessed". But it would basically be the same story as Astarion's, being controlled by some master and freed by the tadpole. Would Larian use the same pattern for two characters? Personally, I hope that's not the case, because this would be a bit repetitive.
But the sentence "A new way of playing" is very interesting, and makes me suspicious.
And if they have a whole route for an origin character who is an antagonist to the others that would certainly be something. Not exactly interesting to me, but it would certainly make the "Evil Route" make more sense.
This is again a wild theory, but maybe this could be the new "Evil Route", playing solo as a Dragonborn cultist, as sort of an antagonist.
I've never played the "Evil Route", not only because I tend to play "good" characters, but also because it didn't make that much sense to me. Even if we get a little bit more power through these tadpoles, the risk of eventually turning into Mindflayers wouldn't be appealing. So why join the cultists?
And even if we somehow knew that we wouldn't turn - we would have to fear that the Absolute could control us, anytime. That doesn't sound like something a power-hungry character would want, I think - being someone else's puppet.
Even for Astarion, who is the only one who profits from the tadpole, it wouldn't make sense to keep the parasite. He would swap one master for another - and since his personal freedom seems to be his top priority, this wouldn't make much sense.
So
maybe - and I know that this is very speculative- they have changed it a bit to have a true "evil route" for a cultist, this Dragonborn, and the "good route" against the cult of the Absolute (though I think it would still be possible to go the "evil route" with other companions).
Maybe they have even made slight changes for our other companions, like they did with Shadowheart, who seems to be much more friendly now than she was in the first patches.
The one thing that doesn't match up for this scenario is that the Dragonborn seems to be under the control of the top-hatted man. This would severely limit the options we would have as players.
Conclusion: I don't know anything and I make wild guesses 😂
I guess we'll have to wait till tomorrow.