My problem with Ren really is that he isn’t menacing. He’s dangerous, yes, but he lacks the underlying menace that is embodied in most of the other films’ villains up to this point. He’s not just a hothead; he’s… he’s a kid with unimaginable powers and a massive chip on his shoulder, rather than being a dark and unquestionably evil soul.
Being dark and unquestionably evil is boring at this point.