It was my understanding that the endings will be influenced by the character's own stats, INT being the central one I'm focusing on for Twilight's (pure?) route. That's mostly because I can't remember what the other three (four? five?) stats are at the moment, and can't find a post with them either, but also because she's a Brain and it fits.
I'm still a little in the dark about the mechanics for the Violet Room, but for the time being I'm working with the knowledge that it's mostly used for stat tweaks, rather than transformation-based. Not that the latter isn't a major component, but for this route I'm not considering that. Maybe having a sliding rule would be good, that Twi can be changed up to a point before one route trips and switches over to the other.