So I met my friend who is not active in the online community at all. For some reason he is 100% confident that Sarada is Sakura's daughter, and he thinks Sasuke's been seeing Sakura regularly and is only hiding from his daughter for some reason. And this is a guy who never shipped and cared about pairings during the entire manga.
When I asked for his reasoning he told me (like I myself said) that chapter 699 clearly indicated a bond between SS with the forehead poke and thanks, which is very important to Sasuke, and that Karin was not even shown in the ending. He also pointed out that Sakura is wearing the Uchiha symbol on her back, living in the Uchiha household, and raising Uchiha Sarada, and we know how much Sasuke values the Uchiha, so he won't take what this woman is doing for granted and will value it greatly. And about Sasuke hiding from Sarada, he can't think of a reason but says that Sakura is in on it too, based on her response to Sarada's glasses question which was very odd. As Sakura of all people would know Sasuke's looks to the millimeter, even if he was away for 200 years. So yes he thinks their relationship is legit and will be handled dramatically.