Hey Dev, i saw your post regarding why you had to rush and so on. I think its pretty cool that you are making your own stuff. As for the other game, its is often that the copy is done faster than the original, because they easily see what can be changed and altered. That said, its also a double edged sword. Because you can do the same thing that he did.
I dont recommend going with AI art, i get why you want to, but i would suggest you stick to your own thing. The biggest difference i see on the two games, is that yours dont really have the same immersion, in a lack of a better word. The story itself seems more rushed (not the work). Which can be a good and a bad thing. But it does prevent you getting the same sort of attachment to the girl.
I would recommend that you consider sticking to your stories, as in multiple people. This gives you the option of setting different types of girlfriends (and potentially boyfriend).
Rather than just having a bunch of messages, you could have the start be a "dating app", where you connect with the girls, and get an idea of what type of person she/he is. Which would again give the players a bigger freedom. Do they want a relationship with a swinger, a hotwife, a cheater, a psycho and so on. And down the line you could have several routes for each. Like taming the psycho or corrupting the housewife. Or just keeping it wholesome and maybe a little boring. Because one thing that is sort of annoying about the games is the lack of choices, or rather consequences of said choices. If i date someone who outright cheats, i want to tell her to pound sand. But if she asks first, i would be inclined to allow her. It becomes a totally different experience.
Capitalize on what you do better, and then perfect that.