I personally don't expect them to make a DLC. DLCs are typically planned out well in advance. And I suspect had Larian planned to make one before the game released, they would've ended the game with far fewer permutations.
For example
during the events of the game really throws a lot of dlc ideas out the window. Being able to murder most of the major characters does the same thing. Additionally including the Emperor also throws dlc ideas out the window as the player could've
(In-fact I wouldn't be surprised if statistically most people do). So you can't exactly make him
the villain or a major character
without retconning it. Which is the laziest solution and would annoy most people.
Historically when most developers attempt to make a dlc post launch with these circumstances they do 1 of 2 things. #1. They create a new protagonist and set the game in a new area. This is the most common thing done as it allows for the most flexibility. #2. They take the same protagonist but they give you entirely different party members and set the game in a new location. This is what occurred with Dragon Age Awakening. The protagonist was still the Grey Warden from DAO, however you had entirely unique party members (with the exception of Oghren who they just retconned him being alive even if the player murdered him). And they just include 1 off easter egg references to past events.
