Hm, I like the restructure, feels like focusing on one girl an update really helps it feel like you make more progress with your sister. And progression is much easier to understand now, the steps make sense now and it's easier to know when events happen during the day. Bugs aside, it's a huge improvement.
The Mom system being mostly absent actually makes the game better, I'm not sure it's needed. The risk of society at large finding out about the incest could function the same. Or if you need a bad guy figure, maybe they should not be so young and thin, porn game logic dictates that if your enemy is a remotely fuckable woman, you gotta give them a good dicking to change the power dynamic.
Fat old grandma coming after your ass with a shoe could work. Tho I understand if it's a pain in the ass to redo the graphics at this point.