Well, I see one very large group. Your mother doesn't make sense without sisters. And when we're talking about sisters, we can't forget about Debbie and Lily. Plus the coffeeshop owner, don't remember her name, but can't see any problems with her in this scenario, and what's more important, can't see her as a part of other group. There are others of course, who's place in a harem is more than questionable, I agree. But the thing is, I don't know, what's harder to make realistic. Harem ending, or ending where MC will leave anyone from that huge group. My problem is that MC acts to them, as a MC of a harem game. Says he love them, care of them, even tells them that he wouldn't leave. Of course I can imagine some events, that can convince MC, but I'm not sure this will be an enjoyable experience. Especially if as you say, girls will brake with MC. Imagine, that the whole game from now, will be just about girls leaving MC for one or another reason. It doesn't sound promising. In the end if something looks like harem game, written like a harem game and plays like one for two years, I want it to be a harem game. Just that simple.