Yeah I get the Meme about Pokemon-"gotta catch them all", but that way it makes the game more complex and will take longer to create the renders this will give less attention to the existing characters who are like a romantic interest, this game is famous for its netori content and if he tries to introduce single sided normal romance would not be worth it when there is no connection to the mc or his milfs, the milfs all know each other and have a relationship so that's why the threesome works so well and not forced.
but, those characters are "added" already.
those are side characters with no planned endings, no problem there.
even more as this game is imo the best netori/milf game being made so far.
i get you wish for your own kinks (bullying others, 3-somes, multisomes), personally i dont care about those at all, yet i do care about exploiting unused hot characters already in the game...at the end, it is what this game is all about, i would say.