I think there would be audience for Solasta2, potentially a bigger one if they invested in production value, but the studio head was open on not being interested in growing too much bigger. I am not sure if they can deliver a worthwhile Solasta2 without doing that. I wouldn't be surprised if they would move on to a different project after S1 is finished.
They have already said in social media posts that their next game after this last DLC will be something entirely new, and not even in the fantasy genre.