Friends in Need is best in the selection above (unfortunately not in the terms of graphics). It lets you decide if you're going to be a knight in shining armor or a complete bastard. And even by acting like an asshole, you have the opportunity to redeem the relationships with some girls later (or have more "fun" humiliating them). So if the game got too dark, it's because of the player and their choices.
Personal Assistant is just a rape and humiliation fest, and if you avoid it, you're just skipping the content. Total meh.
It looks like Lost in Birth lacks a light path, just like Radiant. Either you lust for your daughter, or she lusts for you. The player's choices just change the level of kinkiness. There is no option for a simply father/daughter relationship. I understand how the MC met her mother, what kind of girl she was, and how they made a daughter, but still...
The best game, exploiting the family reunion theme was Connected, imho. But it got abandoned before the actual story began. When I found this game and saw the first chapter, I thought it could be something even better than Connected. But later... you've seen the rest of the chapters.
