Not sure, I don't want to add a lot of gimmicks since in the future Sayako can shapeshift change to Sanako or Ayako and then there is a separation. There is also a mini hidden event during the day off. It is pretty ambitious project which can be a huge red flag as well since a lot of patreon project usually explodes and stuff.
A huge spoiler below
Since I did plan when this game ends, player use Sayako(Sanako and Ayako) for the next story and a Futa Nettori from what I planned. That's why I want to complete this game as best as I can and avoid adding a lot of stuff.