The game takes over a minute to save once you get past the first day. Most of the time, I can get one save to go through, and the game locks up on the next attempt, forcing me to exit the program and play from my last successful save. This is incredibly frustrating.
That said... I have completed multiple playthroughs now in spite of the technical issues. I think that my willingness to endure the frustrating issues with saving speaks volumes about my overall feelings concerning the game.
Kaffekop, sir... you already have something special here, and if it continues to develop as it appears you want it to, it has the potential to be one of the best adult games on the market.
On the surface, there is a situation that looks like your typical "guy living in house with mom and two hot sisters" that has been done dozens of times before. What you have that most of those games lack is a genuinely compelling story backed with top-notch (for the adult game industry) writing and well-developed characters. I'm not talking about specifics here (like exactly which drug Nat was addicted to) so much as the fact that it is obvious to me that you have well-developed outlines for the personalities of all of the characters. Sometimes when you play a game in this genre, you run into a character that might as well be wearing a sign that says "just here for the sex." This isn't even a bad thing in all cases - different games need different types of characters. In Sins of the Father, every character feels distinct from the others, and all of them feel like they contain depth that we have only started to scratch the surface of. In short, you writing is very good, and has turned what would be a forgettable game into something truly intriguing.
However, it isn't just the writing that is good in Sins. Your renders are excellent. While all of your models are, in some way or another, sexy, they are also distinct. Mary actually looks like a 40-something woman. She's very attractive, but not unbelievably so. The same can be said of the other girls around town. Perhaps best of all, there is variety.
I was also a fan of the sex scene in the game and how realistically it was handled. For me, the realism of the scene made it much hotter. Far too many games give their protagonists dicks the size of fire extinguishers only to have all of the female characters in the game completely ignore them other than perhaps being turned on by seeing them. Seeing a character that seems to be a very experienced cougar struggle with handling Mack's equipment made me want to should "IT'S ABOUT FUCKING TIME!" at my monitor.
Obviously, you are well aware of the technical issues that currently plague your game, and I fully support your decision to move the game to a platform that works better for you. I am actually more sympathetic than you might think, as I have been considering making my own game for about a year now and have been reluctant to do so due to my lack of experience with DAZ and coding. In fact, your own struggles with Unity have just about convinced me that I need to bite the bullet and spend a few weeks learning Renpy (I had been debating on using Unity vs. using Renpy).
I hope you don't lose faith in this project because of your technical struggles. The world needs more games like this one (or like what this one has the potential to become) and more good writers with good stories to share.