I actually like Fulgrim's fall, as a story (or at least the parts I've read). I think the people saying that picking up the sword takes away any agency from him are wrong and need to read the books. I think as he is written he is one of the better choices for a daemon primarch of Slaanesh. I just don't think he benefited that much from falling, if at all.
‘if only fulgrim didn’t pick up the sword he could have’ could have what. could have what. stayed under the oversight of a distant father figure? kept pressuring himself and his sons to be perfect and flawless all the time? been disposed of when he’d served his purpose? i hate you