We already have had a long conversation about that in Divinity 2 section of the forums. And not just one. Unfortunately, such mistakes are unavoidable when it comes to RPG videogames, especially if the sequel weren't actually (read: solid planing) planned from the beginning.
Unlike with the books (belletristic ie fantasy), the game isn't always about the story and setting, a lot of it dedicated to visuals, audio setup and gameplay. Sometimes the latter can be so good that saves bad storywriting/setting (and vice versa).
