Not everything needs to be relegated to the trash compactor room, right?
First Appearance: 'The Last Command' by Timothy Zahn
Novelization: As the son of Han and Leia, Jacen inherited both Force sensitivity and a reckless streak. Starting out as a promising young Jedi, Jacen slowly but surely turned to the Dark Side with his willingness to do whatever it takes to keep the galaxy safe. By the time he reached adulthood, the eldest son of the New Republic's heroes had become Darth Caedus. Falling into the same trap as his grandfather, his attempts to avert the prophecy of a dark figure ruling the galaxy with an iron fist only hastened his transformation into said figure.
Potential Screen Adaption: The Star Wars universe loves a good parallel and Jacen/Caedus follow the same cadence as Anakin and Luke Skywalker before him. However, unlike he grandfather and uncle, Jacen's story twists away from their redemption arc to explore what happens when a person can't and/or doesn't want to be saved.
Casting Suggestion: Sam Claflin