The switch from 3D to 2D came from a desire of the creator to change the means of story telling. they wanted to switch engines ( and have discovered they like using Renpy MUCH more) and because they wanted to change how the content was created. their work before the story was created episodically. essentially they would write and build the chapter, then write from there. This game has all of the characters content, and paths written out before hand so it all makes as much sense as possible and allows for planned progression.
They also wanted to feature a different art style than rendered 3d models and has spent the past year developing their own art skills to create the models personally. if you go through the patreon they have improved significantly over the year and will continue to do so. have faith, it will be a good game. Also, as Demoness said above, the girls are; School Teacher (doting mother hen), Oldest Daughter (Best Friend and "Lesbian"), Youngest Daughter (not best friend [dislikes you]), and Father's New Wife (Step Mother [physically abusive and hates you]). no planned incest. The MC is a character that had no confidence and was beaten by his father and step mother. after his teachers oldest daughter took a liking to him she decided to make him her work out partner, as she enjoys fitness. When the introduction ends you are now a formerly abused MC who has new physical fitness and confidence that he doesn't exactly know how to use. and will use his time with the girls to discover that.