Use the walkthrough with her. You can fuck around some but only for a while, like with the swingers. You must avoid the Doc girl from the conference, the assistant, invite Claudia and the daughter to the festival, help her with the investigation, not to bust in front of the husband, hire her for work of course, not to have anyone moved in when she arrives, don't promise the daughter that you'll get back her parents together, agree when you asked if she's your girlfriend around new year, I also haven't accepted the money from the mom, don't let her husband to go to jail, I'm not sure if I let her move out or not, I think I did, she came back eventually. Other than these, I don't remember anything significant right now, as for the points, after a while it should be clear which choices are the best for her, but you can always rollback if her reaction isn't good enough.
I don't remember what the NTR was about, like who's Rita. Now you can turn it off though as it says in the changelog. For recommendation...well that's a tricky one. It's basically a doctor simulator, there's many trials and errors, you should defo use the walkthrough, and I don't know about the visual novel mode, but the original was a massive grindfest, the type that I won't ever replay again, even if I'd be interested in some of the other routes.
I managed to get it almost at first try, had to go back and be tricky about the assistant doc I think though. Other than that, with the wt, it's doable. She basically likes when you nice, hates when you're an ass, and family is a priority for her. Instead of being obnoxious, you have to be subtle and let her feelings develop naturally. I even managed to finish the game 3 months earlier than the wt said it would end.